A MAGYAR MITTEILUNGEN
TUDOMANYOS AKADEMIA DER
CSILLAGVIZSGALO STERNWARTE
INTEZETENEK DER UNGARISCHEN AKADEMIE
KOZLEMENYEI DER WISSENSCHAFTEN
BUDAPEST - SZABADSAGHEGY
Nr. 76.
L. SZABADOS
PHOTOELECTRIC UBV PHOTOMETRY
OF NORTHERN CEPHEIDS, II
BUDAPEST, 1980
ISBN 963 8361 02 6 osszkiadas
HU ISSN 0324-2234
Felelos kiado: Szeidl Bela
PHOTOELECTRIC UBV PHOTOMETRY OF NORTHERN CEPHEIDS, II
ABSTRACT
New UBV photoelectric observational data on 42 northern Cepheids with periods of 5-10 days
are presented. The period changes and the variations in the light curve of the observed Cepheids
are investigated. No secular light curve variation has been discovered.
The O-C diagrams of CV Mon and RS Ori show a period jump and a subsequent rejump to the
earlier value of the period. These two Cepheids as well as the shorter period ones with a
rejumping period are probably members of binary systems. Another effect can be pointed out in
AW Per and DD Cas which are also members of binary systems: the apparent period changes due to
the orbital motion around the common centre of gravity can be seen. Both the orbital period and
the value of a*sin i can be determined for these latter two stars. The combined effect (i.e. the
effect of the orbital motion and the rejumping period) can be seen in the O-C diagram of the
short period Cepheid SU Cygni.
INTRODUCTION
This paper is the second part of a series dealing with the new UBV photometry of
northern Cepheids performed at the Konkoly Observatory, and it contains the observational
data and O-C diagrams of Cepheids with periods longer than 5 days but shorter than 10 days.
The first part of this Cepheid survey included Cepheids with periods shorter than 5 days
(Szabados 1977, hereinafter this paper is referred to as Paper I). The third part will
cover the longest period Cepheids (P > 10 days).
The original purposes outlined in Paper I were as follows:
1. To search for double-mode Cepheids in the northern sky;
2. To investigate period changes;
3. To examine secular variations of the light curves provided that they can be determined;
4. To obtain photoelectric light curves of those Cepheids which
have not previously been observed photoelectrically.
Since the existence of the beat phenomenon in the case of
Cepheids with periods longer than five days is improbable, the first item may hardly be a
real aim when observing Cepheids with periods as long as 5 days or more.
Item 4 also has less importance because the overwhelming majority of the stars dealt
with in this programme has been observed photoelectrically; however, photoelectric photometry of
several faint Cepheids was carried out for the first time as
recently as in the seventies (Pel 1976, Wachmann 1976). The major
contribution of the present photoelectric observations towards
developing our knowledge about the light curves of the Cepheids
is that the observational points are well spread in phase on the
normal light curves. There are at least a dozen Cepheids in this
sample the periods of which are almost equal to an integer (e.g.
VW Cas: P=5.994d; BK Aur: P=8.002d), thus it is impossible to
obtain a complete light curve of these variables at a given
geographical longitude during one observational season. The present
photometry carried out between 1974 and 1978 yielded reliable
photoelectric light curves for this rather arbitrary group too.
After having revealed the existence of period rejumps in
Paper I, the investigation of period changes is the most important
purpose. The term rejump was introduced in Paper I.
During the course of this present part of the work 42 Cepheids and
one star which subsequently proved to be non-variable
were observed. Of these 43 stars, 19 were observed in three colours
of the UBV system, the other 24 in B and V lights only.
THE OBSERVATIONS
The stars dealt with in this programme were selected from
the General Catalogue of Variable Stars (Kukarkin et al. 1969-
1970) and from the current astronomical literature, with the
restrictions that their declination should be north of 0 and B
magnitude (or mpg for lack of photoelectric observations) at
light minimum brighter than 12.5mag. This sample contains Cepheids
strictions that their declination should be north of 0 and B
of both populations with a period 5d < P < 10d.
The stars investigated are listed in Table 1. The number of
observations on each star, the colours, serial numbers of the
pages where the individual observations and the O-C diagram with
additional remarks on the given star can be found are indicated
in the successive columns. The total number of observations is
804. The star V 1165 Aql is not a Cepheid variable. Judging by
present photometry this star is a non-variable, but very small
amplitude light variations cannot be ruled out. The observational
data and a detailed analysis on V 1165 Aql are published
Table 1 The programme
Page Page
Star N Col. obs. rem. Star N Col. obs. rem.
FM Aql 20 UBV 10 54 GH Cyg 19 BV 18 87
FN Aql 18 UBV 10 108 MW Cyg 18 BV 19 49
KL Aql 18 BV 10 52 V 386 Cyg 18 BV 19 29
V 336 Aql 18 BV 11 81 V 538 Cyg 19 BV 20 55
V 600 Aql 18 BV 11 80 V 924 Cyg 18 BV 20 46
V 733 Aql 19 BV 11 58 TX Del 20 UBV 20 56
V 1165 Aql 9 BV - 4 W Gem 17 UBV 21 93
eta Aql 20 UBV 12 73 RZ Gem 19 BV 21 44
AO Aur 16 BV 13 72 BB Her 20 BV 22 83
BK Aur 18 UBV 13 99 X Lac 19 UBV 22 42
RX Cam 23 UBV 14 91 RR Lac 19 UBV 23 66
RS Cas 19 BV 14 62 BG Lac 17 UBV 23 30
SW Cas 21 BV 14 40 CS Mon 20 BV 24 71
VV Cas 17 BV 15 59 CV Mon 18 BV 24 39
VW Cas 18 BV 15 50 RS Ori 23 UBV 25 85
DD Cas 19 BV 16 109 GQ Ori 23 UBV 25 105
DL Cas 13 UBV 16 98 AW Per 23 UBV 25 68
FM Cas 17 BV 16 47 HR 690(Per) 18 UBV 26 84
IX Cas 19 BV 17 106 S Sge 20 UBV 26 101
CR Cep 19 BV 17 61 U Vul 20 UBV 27 95
delta Cep 19 UBV 17 32 X Vul 21 UBV 28 64
VY Cyg 17 BV 18 89
Figure 1a-f Identification chart
elsewhere (Szabados 1979).
A full description of the observational technique, the
telescopes and filters used can be found in Paper I (p. 6). The V
magnitudes and colour indices of the comparison and check stars
are listed in Table 2. The tie in observations were made with
the aid of UBV standard stars taken from the catalogue of Blanco
et al. (1968). An asterisk instead of the name of the star in
Table 2 denotes that the star is not in the Bonner Durchmusterung,
in which case the identification charts in Fig. 1a-f should
be consulted. In these charts the letter a denotes the comparison
star and the star marked b is the check one. The size of the
charts is about 25'x25' except for VW Cas (40'x40'); north is at
the top.
The comparison between the present photometric system (UBV_{sz})
and Schaltenbrand and Tammann's (1971) standard one (UBV_{scht})
gives the following transformation formulae:
V_{SZ} = 0.997V_{scht} + 0.026 (38 common stars)
B_{SZ} = 0.993B_{scht} + 0.083 (38 common stars)
U_{SZ} = 1.002U_{scht} - 0.021 (17 common stars)
Table 3 contains the observations in alphabetical order of
the constellations. The observations made with the 20" telescope
are marked with asterisks in the column of the Julian Date. Some
unpublished observations made by Prof. L. Detre in 1953 and by
Dr. J. Abaffy in 1967 are also listed in Table 3. Unfortunately,
since the comparison stars used by them are unknown in several
cases these two sets of observations have not been transformed
to the standard system, and only the magnitude differences are
given in the instrumental system.
THE LIGHT CURVES AND PERIOD CHANGES OF THE INDIVIDUAL VARIABLES
This section contains the light curves, the tables and the
graphs of the O-C values and some remarks on the observed Cepheids.
It was not my intention to give the full history of the
variables which would have increased considerably the volume of
this paper. The variables were arranged according to the length
of their period as in Paper I.
The light and colour curves are constructed from the observations
Table 2
Variable Comp. V B-V U-B Check V B-V U-B Remark
FM Aql +10 3813 7.09m 1.42m 1.09m +10 3801 7.13m 1.92m 2.03m
FN Aql + 3 3938 9.31 1.26 1.21 + 4 4009 variable 1
KL Aql * 10.04 1.47 +15 4019 9.72 0.34 2
V 336 Aql + 0 4078 10.03 0.78 + 0 4081 10.57 0.71
V 600 Aql + 8 4050 10.41 0.71 + 8 4049 10.60 0.72
V 733 Aql +10 4111 10.41 0.64 +10 4110 9.55 0.55
eta Aql + 6 4357 3.71 0.86 0.49 + 2 3879 3.36 0.33 0.04
AO Aur * 11.10 0.78 * 11.03 1.23
BK Aur +49 1310 9.43 0.40 0.08 +49 1319 9.74 0.43 0.06
RX Cam +58 687 8.14 1.36 0.95 +58 672 8.31 0.64 0.20
RS Cas +61 2481 9.91 1.12 +61 2492 9.20 0.16 3
SW Cas +57 2694 9.75 0.60 +57 2689 8.39 0.34 3
VV Cas +59 327 10.40 0.71 +59 325 9.60 0.33
VW Cas +60 145 10.12 1.23 * 10.58 0.55
DD Cas +61 2577 10.06 1.12 +61 2576 9.82 0.37 3
DL Cas +59 67 8.88 0.97 0.64 +59 72 8.92 0.25 0.18
FM Cas +55 29 9.16 1.67 +55 28 9.18 0.30
IX Cas * 10.69 0.41 * 10.75 1.26
CR Cep * 10.26 1.18 * 10.34 0.69
delta Cep +57 2475 3.32 1.51 1.79
VY Cyg +39 4425 10.74 1.01 +39 4426 possible varies 4
GH Cyg +29 3835 9.72 1.10 +28 3565 10.39 0.58
MW Cyg +32 3738 9.33 1.14 +32 3739 9.31 0.33
Table 2 (cont.)
Variable Comp. V B-V U-B Check V B-V U-B Remark
V 386 Cyg +41 4062 8.63m 1.63m +40 4455 10.23m 0.22m
V 538 Cyg +50 3397 9.88 1.21 +50 3395 9.98 1.02
V 924 Cyg +32 3498 9.77 0.31 +32 3499 10.46 0.20
TX Del + 2 4257 9.27 0.20 0.15m + 2 4256 8.86 0.07 0.15m
W Gem +15 1230 7.17 0.69 0.29 +15 1255 7.36 0.25 0.10
RZ Gem +22 1141 10.31 0.47 +22 1148 9.65 0.52
BB Her +12 3652 9.66 0.65 +12 3640 10.22 0.23
X Lac +55 2830 7.37 0.56 0.11 +55 2827 8.45 0.21 0.15
RR Lac +55 2792 8.71 0.24 -0.06 +55 2791 8.79 1.05 0.83
BG Lac +42 4273 8.64 0.68 0.39 +42 4275 9.14 0.59 0.06
CS Mon * 10.70 0.19 * 10.72 0.28
CV Mon + 3 1319 10.10 1.55 + 3 1317 10.21 1.88
RS Ori +14 1260 8.32 0.69 0.22 +15 1176 8.06 0.29 -0.46
GQ Ori + 9 1117 8.85 0.37 0.21 + 9 1121 9.79 0.32 0.18
AW Per +37 968 7.77 1.30 1.03 +36 948 6.73 1.14 1.03
HR 690 +55 598 5.18 0.37 -0.11 +54 539 7.58 0.10 -0.15
S Sge +16 4121 5.79 0.62 0.12 +16 4081 6.02 0.02 -0.15
U Vul +20 4210 6.48 1.08 0.98 +20 4218 6.54 0.42 -0.48
X Vul +26 3739 8.87 0.30 0.17 +26 3746 9.55 0.16 0.08
Remarks: 1 The star BD +4 4009 is a new Cepheid variable (Kovacs and Szabados 1979).
2 The check star has a faint companion within the edge of the diaphragm.
3 The comparison star has a faint companion within the edge of the diaphragm.
4 The check star is a suspected variable. The available observations do not allow
to determine the type of the variability.
Table 3 The observations
FM Aquilae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2229.521 8.63 1.45 0.92 2673.294 8.15 1.25 0.88
2277.419 8.39 1.46 0.94 2708.258 8.14 1.31 0.76
2297.338 8.64 1.48 1.06: 2900.514 8.30 1.46 0.92
2304.375 8.41 1.36 0.78 2939.526 8.64 1.47: 0.98:
2308.315 8.49 1.45 0.86 2971.395 8.06 1.22
2591.433 8.54 1.45 0.78: 2976.399 8.63 1.41 0.93
2620.459 8.50 1.44 0.95 3287.553 8.68 1.43 0.98
2623.449 7.96 1.13 0.74 3340.389 8.24 1.39 0.83
2642.338 8.04 1.26 0.68: 3363.461 7.96 1.17 0.71
2669.333 8.50 1.54 0.86 3705.366 7.89 1.16 0.71
FN Aquilae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2277.376 8.39 1.23 0.97 2673.318 8.26 1.07
2297.316 8.53 1.33 2708.247 8.64 1.31
2304.320 8.22 1.16 0.83: 2871.597 8.37 1.13 0.98
2308.297 8.74 1.38 1.13 2900.567 8.26 1.09 0.92
2523.581 8.31 1.28 0.98 2960.468 8.40 1.30
2589.444 8.31 1.13 3287.531 8.53 1.23
2620.385 8.62 1.34 1.11 3337.519 8.22 1.14
2623.434 8.61 1.21: 1.09: 3390.380 8.74 1.40 1.11
2669.317 8.75 1.39 1.09 3705.378 8.47 1.20
KL Aquilae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2904.556 9.97 0.90 3275.539 10.52 1.13:
2960.519 9.95: 0.84: 3337.413 10.46 1.08
2990.415 9.85 0.82 3340.467 10.18 1.01
3016.368 10.12 1.05: 3342.464 10.52 1.17
3075.239 10.16 0.95 3363.429 9.84 0.82
3078.250 10.22 1.08 3382.345 9.98 0.86
Table 3 (cont.)
(KL Aql)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
3390.368 10.35 1.11 3761.315 9.98: 1.06:
3476.189 10.42 1.15 3795.309 10.47: 1.21:
3722.511 10.29 0.95: 3800.250 10.55: 1.17:
V 336 Aquilae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2276.367* 9.72 1.31 3075.212 10.29: 1.46:
2299.287* 9.98 1.44 3092.202 9.50 1.23:
2302.298* 9.84 1.30 3342.436 9.77 1.30
2548.503* 10.09 1.42: 3350.412 9.81 1.41
2712.205* 9.51 1.15 3351.493 10.01 1.51
2976.387 9.69 1.22 3390.303 10.00 1.44:
2990.364 9.56 1.20 3425.240 10.18 1.55
3046.270 10.25 1.39: 3763.326 9.74 1.29
3064.246 9.79 1.21 3800.228 9.60 1.09:
V 600 Aquilae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2276.382* 9.97 1.52 2976.363 9.73 1.37:
2299.415* 10.20 1.65: 2990.343 9.92 1.37
2302.314* 10.13 1.53: 3046.286 10.34 1.66
2623.403 9.90 1.55 3064.259 9.87 1.45
2634.429 10.37 1.60 3304.515 10.05 1.50:
2636.474 9.73 1.32: 3342.449 10.30 1.64
2900.532 10.25 1.60 3390.326 9.95 1.50
2904.538 9.78 1.37 3401.336 10.40 1.68
2960.504 10.33 1.54 3435.224 10.12 1.61
V 733 Aquilae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2276.396* 9.73 0.85 2277.464 9.84 1.01
Table 3 (cont.)
(V 733 Aql)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2278.469 9.96 1.03 2669.297 10.17 1.06
2289.358 9.87: 0.84: 2712.243* 10.16 1.04
2291.330 10.10 1.01 2715.231 9.74 0.86
2299.454* 10.00 0.92 2904.521 10.04: 1.12:
2302.398* 9.90 1.04 3075.228 9.92 1.03
2304.341 10.09 1.09 3078.234 9.97 0.90
2356.232 9.72 0.80 3388.374 9.75 0.85
2522.582 9.80 0.86 3403.286 10.06 1.02
2543.535 9.94 0.99
eta Aquilae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2277.442 3.78 0.72 0.39 2708.272 3.60 0.61 0.34
2289.377 4.18 0.94 0.84: 2720.212 4.22 0.99 0.75
2591.487 4.30 0.97 0.79 2960.423 3.61 0.63 0.37
2620.507 4.30 0.99 0.72 2990.376 3.80 0.80 0.54
2622.495 3.58: 0.59: 0.31: 3030.341 4.13 0.86 0.54
2623.482 3.67 0.71 0.45 3046.301 3.59 0.66:
2642.369 4.27 0.97 0.69 3350.426 4.02 0.89 0.67
2645.405 3.78 0.74 0.47 3363.362 3.82 0.77 0.53
2669.305 4.07 0.93 0.70 3382.306 3.96 0.78 0.47
2675.310 3.85 0.84 0.51 3386.300 4.00 0.90 0.53:
Observations in 1953
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2430000+ 2430000+
4581.561 4.35 1.01 4605.319 3.91: 0.82: 0.42:
4583.412 4.13 0.84 0.59 4606.366 3.59 0.66 0.35
4584.428 3.58 0.60 0.45 4608.349 3.79 0.82 0.62
4585.434 3.69 0.71 0.48 4609.419 4.09 1.00 0.58
4588.447 4.26 0.98 0.72 4614.417 3.71 0.79 0.45
4600.371 3.79 0.81 0.60 4619.354 4.04 0.85 0.53
4601.543 3.73 0.91 0.57 4621.415 3.72 0.74 0.45
4602.348 4.20 0.90 0.71 4622.393 3.92 0.93 0.72
Table 3 (cont.)
(eta Aql)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2430000+ 2430000+
4623.378 3.95: 1.00: 0.51: 4642.308 3.56 0.68 0.44
4624.438 4.35: 0.90: 0.77: 4653.316 4.29 1.08
4625.376 4.47: 0.95: 0.87: 4654.382 4.40 0.99 0.63
4626.370 4.24 0.86 0.67 4656.296 3.61 0.60 0.39
4627.363 3.84: 0.69: 0.35: 4660.313 4.19 0.99 0.73
4628.408 3.64 0.73 0.29 4663.277 3.54 0.65 0.46
4629.323 3.80 0.83 0.47 4664.276 3.77 0.77 0.41
4630.378 3.89 0.87 0.63
AO Aurigae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2424.407* 10.57 0.98 2775.336* 10.37: 0.88:
2453.457 10.95 1.13 2776.370* 10.65 1.02
2473.259 10.90 1.12 2816.264 10.55: 0.83:
2711.553* 11.21 1.28: 3124.470 11.19 1.29
2712.522* 11.30 1.28 3192.369 11.31 1.24
2715.594 10.75 1.05 3214.302 10.70 0.83
2743.488* 10.82 1.08 3423.544 10.94 1.09
2756.532 10.83 1.06 3789.499 10.44 0.83
BK Aurigae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2404.597 9.54 1.15 0.76 2794.233 9.25 0.95 0.66
2443.408 9.27 1.03 0.52: 2816.242 9.58 1.04 0.68
2448.489 9.41 1.00 0.55 2829.266 9.62 1.15: 0.85:
2450.431 9.27 1.00 0.63 2831.253 9.78 1.26: 0.88:
2453.493 9.68 1.20 0.74: 3163.212 9.29 1.01 0.65
2454.363 9.82 1.23 0.92 13524.224 9.41 1.12 0.75
2455.463 9.73 1.17 0.84 3560.257 9.66 1.11 0.75
2465.278 9.13 0.92 0.60 3598.282 9.75 1.26
2468.251 9.50 1.15 0.64: 3849.470 9.21 0.92 0.59:
Table 3 (cont.)
RX Camelopardalis
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2369.467 7.90 1.32 0.97 2767.339 7.44 1.17 0.75
2404.567 7.44 1.22 0.85 2777.455* 7.69 1.33 0.99
2424.357* 8.02 1.44 1.02 2794.427 7.82 1.40
2443.388 7.48 1.22 0.81 2831.303 7.50 1.20 0.84
2450.412 7.34 1.10 0.73 2850.277 7.95 1.43
2453.477 7.72 1.36 1.01 3217.278 7.38 1.11 0.78
2455.442 8.02 1.44 1.13 3219.280 7.47 1.20 0.78
2460.315 7.46 1.20 0.73: 3390.548 7.73 1.27 0.93
2465.305 7.51 1.20 0.74: 3437.348 7.98 1.39 1.00
2473.384 7.45 1.13 0.75 3481.298 7.55 1.29 0.92
2676.497 7.97 1.45 1.11 3490.353 7.78 1.33:
2756.465 8.01 1.48 1.13:
RS Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2299.567* 10.33 1.63 2776.405* 10.04 1.60
2424.233* 10.17 1.61 2777.336* 10.24 1.62
2426.222* 10.09 1.49 3163.255 9.83 1.38
2710.416* 9.57 1.27 3340.496 9.58 1.33
2711.496* 9.74 1.42 3342.479 9.98 1.59:
2712.389* 9.94 1.51 3388.399 10.36: 1.56:
2715.466 10.22: 1.59: 3390.563 9.56 1.28
2738.406 10.03 1.54 3425.529 10.21 1.66:
2743.301* 9.80 1.43 3490.389 10.01 1.46
2756.219 9.95: 1.48:
SW Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2364.330 9.43 1.03 2645.525 9.96 1.22
2397.263 9.48 1.08 2712.293* 9.36 1.03
2407.340 9.35 0.96 2715.447 9.87: 1.29:
Table 3 (cont.)
(SW Cas)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2720.414 9.83 1.25 3340.403 9.79 1.23
2738.295 9.88 1.13 3342.492 9.67 1.10
2990.556 9.52 1.08 3363.499 9.98 1.24
3045.330 9.58 1.13 3437.486 9.67 1.17
3045.572 9.63 1.19 3476.235 9.77 1.26
3140.228 9.98 1.27 3481.262 9.74 1.25
3163.238 9.52 1.02 3490.218 9.34 1.01
3337.537 9.44 0.94
VV Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2424.268* 10.98 1.28 2816.299 10.98: 1.39:
2710.489* 11.08 1.30: 3078.365 10.66 1.12
2711.536* 11.12 1.33 3124.449 10.72 1.27
2715.569 10.84 1.33 3140.197 10.91 1.23
2743.449* 10.39 1.01 3375.538 11.18 1.27:
2775.295* 10.37 1.06 3390.456 10.62: 1.12:
2776.387* 10.64 1.22 3437.367 11.17 1.33
2777.337* 10.79 1.26 3483.265 10.45 1.14
2787.250 10.28 0.94
VW Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2424.283* 10.79 1.16 2776.211* 11.00 1.27
2426.253* 10.59 1.15 2777.194* 11.04 1.36:
2710.474* 10.99 1.31 2990.502 10.74 1.13
2711.524* 10.97 1.27 3045.601 10.96 1.25
2712.486* 10.45 1.06 3048.457 10.37 1.06
2715.548 10.88 1.22 3124.431 11.05 1.32
2738.445 10.70 1.14 3390.441 10.42 1.07
2743.430* 10.44 1.13 3425.510 10.58 1.05
2756.192 10.71 1.11: 3524.295 10.70 1.19
Table 3 (cont.)
DD Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2407.320 9.63 1.11 2776.423* 10.18 1.34
2424.328* 9.97 1.23 3045.547 9.59 1.10
2685.526 9.88 1.42 3162.287 9.70 1.11
2710.458* 9.80 1.14 3337.526 9.92 1.24:
2712.433* 9.64 1.14 3363.487 10.02 1.45
2715.509 9.97 1.41 3390.427 9.70 1.24
2743.375* 9.77 1.29 3425.427 9.98 1.19
2756.417 10.11 1.39 3426.317 9.83 1.14
2767.247 10.07 1.28 3772.468 9.70: 1.23:
2775.277* 10.16: 1.41:
DL Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2308.580 8.69 1.05 0.78 2777.420* 9.26 1.30 0.80:
2685.558 8.84 1.11 0.78 2787.217 8.97: 1.05: 0.69:
2712.473* 9.15 1.31 0.77 2990.515 8.85 1.14 0.83
2715.527 8.79 1.07 0.83: 3490.201 9.22 1.28
2738.421 9.11 1.29 0.74 3560.239 9.11 1.28 0.79
2743.410* 9.01 1.25 0.78 3830.210 8.84 1.09 0.72
2756.262 8.72 1.05 0.70
FM Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2397.283 9.44 1.19 2794.256 8.91 0.89
2407.357 9.19 1.12 2816.277 9.44 1.15
2685.541 9.11 1.05 3140:242 9.31 1.16
2712.447* 9.12 0.96 3364.564 9.00 0.89:
2743.390* 9.15: 0.98: 3375.500 8.83 0.85
2756.438 9.23 1.14 3390.354 9.34 1.19
2767.263 9.12 1.12 3438.285 9.21 1.06
2775.255* 9.48 1.11: 3546.232 9.22 1.12
2777.399* 8.92 0.91
Table 3 (cont.)
IX Cassiopeiae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2276.568* 11.24 0.61 3050.496 11.69 0.75
2299.586* 11.72 0.86 3075.271 11.36 0.79
2424.250* 11.27 0.67 3162.304 11.34: 0.68:
2426.236* 11.55 0.78 3163.271 11.22 0.63
2710.436* 11.65 0.86 3382.402 11.32 0.60
2711.515* 11.69 0.77 3385.373 11.33: 0.53:
2712.403* 11.65 0.76 3390.576 11.56 0.68
2743.551* 11.19 0.59 3403.443 11.19: 0.61:
2777.374* 11.59: 0.68: 3426.479 11.69 0.71
3048.585 11.50 0.85
CR Cephei
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2318.428 9.53 1.45 2756.315 9.53 1.39
2350.420 9.48 1.36 2775.316* 9.57 1.40
2623.503 9.68: 1.45: 2777.291* 9.74 1.50
2685.476 9.72 1.53 2990.542 9.78 1.54
2712.378* 9.45 1.38 3075.256 9.54: 1.47:
2715.316 9.76 1.54 3163.223 9.67 1.56
2720.319 9.66 1.46: 3375.440 9.70 1.60:
2728.291* 9.81 1.53 3382.537 9.79 1.48
2738.276 9.53 1.50 3403.378 9.46 1.34
2743.281* 9.45 1.35
delta Cephei
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2318.384 4.02 0.78 0.52 2645.432 3.91 0.72 0.52
2365.323 3.63 0.57 0.40 2646.365 4.13 0.78 0.63
2591.498 3.84 0.69 0.48 2669.370 4.33 0.84 0.64
2620.418 4.27 0.85 0.63 2675.383 3.88 0.65 0.39
2622.546 3.51 0.50 0.33 2676.413 3.58 0.51 0.39
Table 3 (cont.)
(delta Cep)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2756.293 3.50 0.46 0.36 3340.416 4.20 0.78 0.54
2767.209 3.53: 0.42: 0.34: 3342.509 3.73 0.67:
2787.230 4.32 0.86 0.68 3390.540 3.69 0.59 0.37:
3043.480 3.99 0.63: 0.47: 3403.365 4.17 0.79 0.64
3048.471 4.03 0.79 0.53
Observations in 1967
J.D.hel. Deltav Delta(b-v) Delta(u-b) J.D.hel, DeltaV Delta(b-v) Delta(u-b)
2430000+ 2430000+
9787.385 +0.916 -0.566 -1.030 9808.428 +0.854 -0.550 -1.058
9791.462 +0.651 -0.566 -1.126 9809.431 +0.814 -0.625 -1.196
9795.320 +0.337 -0.772 -1.226 9810.266 +0.028 -0.909 -1.359
9796.506 +0.562 -0.597 -1.106 9812.305 +0.537 -0.662 -1.128
9799.335 +0.159 -0.864 -1.385 9821.285 0.000 -0.884 -1.356
9806.331 +0.389 -0.724 -1.219
VY Cygni
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2307.424 9.32 1.12 3287.466 9.80 1.43
2634.498 9.96 1.46 3363.442 9.62: 1.36:
2685.411 9.46 1.11 3375.549 9.25 1.06
2712.318* 9.89 1.43 3382.436 9.58 1.16
2714.318 9.56: 1.29: 3425.280 9.43: 1.24:
2715.291 9.20: 1.09: 3524.198 9.36 1.07
2743.262* 9.77 1.40 3716.500 9.74: 1.28:
3050.509 9.92 1.44 3724.471 9.63: 1.32:
3275.507 9.43 1.16 3761.326 9.46 1.08
GH Cygni
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2276.421* 9.65 1.21 2636.504 9.76 1.19
2302.462* 10.11 1.44 2639.491 10.31 1.37
2634.536 9.61: 1.11: 2712.257* 9.51 1.10
Table 3 (cont.)
(GH Cyg)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2715.253 9.90 1.30 3342.529 10.18 1.42
2728.243* 9.50 1.11 3375.413 10.22 1.24
2743.187* 9.62 1.16 3385.488 9.68 1.07
2927.493 10.12 1.35 3388.385 10.05 1.29
2960.438 10.29 1.34 3401.351 9.64 1.15
3227.620 9.86 1.17 3438.296 10.12 1.12:
3340.449 9.81 1.22
MW Cygni
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2634.461 9.52 1.45 2927.477 9.82 1.52
2639.537 9.44 1.34 3046.316 9.69: 1.49:
2685.393 9.23 1.20 3227.608 9.16 1.20
2712.301* 9.60 1.50 3275.524 9.17 1.22
2720.263 9.77 1.46 3342.541 9.49 1.38
2728.259* 9.27 1.32 3385.473 9.72 1.47
2743.222* 9.81 1.56 3401.435 9.33 1.33
2777.209* 9.49 1.45 3435.244 9.51 1.32
2904.477 9.77: 1.63: 3490.179 9.25 1.23
V 386 Cygni
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2307.446 9.98: 1.68: 2776.237* 9.77 1.63
2634.516 9.65 1.57 2777.251* 9.26 1.42
2636.537 9.52 1.65 2928.417 9.87 1.76
2685.428 9.84 1.69 3078.390 9.57 1.63
2714.335 9.31 1.40 3363.376 9.81 1.65
2720.285 9.45 1.55 3420.446 9.67 1.61
2728.276* 9.89 1.76 3426.285 9.77 1.66
2738.261 9.90 1.71 3476.205 9.31 1.38
2767.224 9.31: 1.50: 3481.213 9.48 1.47
Table 3 (cont.)
V 538 Cygni
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2276.530* 10.40 1.25 2776.259* 10.61 1.47
2299.533* 10.71 1.46 2948.438 10.75 1.42
2302.410* 10.29 1.23 3075.431 10.64: 1.30:
2424.198* 10.21 1.18 3078.348 10.35 1.18
2426.194* 10.45 1.39 3337.357 10.41 1.34
2634.556 10.55 1.31: 3340.530 10.71 1.39
2636.555 10.71 1.46 3363.391 10.63 1.43
2639.521 10.42: 1.25: 3403.431 10.25 1.15:
2666.341 10.60: 1.55: 3426.349 10.60 1.32
2712.342* 10.27 1.25
V 924 Cygni
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2276.408* 10.63 0.86 3227.591 10.59 0.76
2299.518* 10.76 0.94: 3275.491 10.77: 0.99:
2302.447* 10.54: 0.82: 3287.414 10.78 0.87
2712.270* 10.73 0.94 3304.406 10.82: 0.81:
2715.271 10.56 0.83 3375.483 10.89: 0.86:
2900.550 10.69 0.91 3390.398 10.62 0.88
2927.461 10.58 0.80 3401.321 10.63 0.84
2948.424 10.65 0.83 3437.309 10.85 0.90
3064.275 10.80 0.88 3438.309 10.70 0.84
TX Delphini
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2.440000+
2277.486 9.29 0.84 0.76 2379.187 8.94 0.59 0.52
2297.430 9.45: 0.97: 0.79: 2591.530 9.18 0.78
2299.468* 8.69 0.54 0.45 2623.466 9.42 0.91 0.74:
2304.356 9.29 0.77 0.69 2634.395 9.11 0.74 0.77:
2307.387 9.07 0.75 0.67 2666.300 9.37 0.86
2343.261 8.94 0.55: 0.47: 2960.536 9.00 0.70 0.65
Table 3 (cont.)
(TX Del)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2990.402 8.88 0.55 0.51 3426.299 9.49 0.88 0.94
3351.517 9.49 0.94 0.97: 3481.242 9.53 0.95 0.89
3386.338 9.05 0.74 0.59 3743.438 9.02 0.64 0.56
3390.316 9.00 0.62 0.57 3772.307 9.17 0.65 0.61
W Geminorum
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2404.497 7.34 1.15 0.92 2756.505 6.81 0.84 0.67:
2429.452 7.15 1.02 0.65 2767.475 7.17 1.14 0.80:
2432.425 6.72 0.89 0.63 2794.405 6.73 0.69: 0.53:
2443.448 7.22 1.15 0.95: 2841.338 6.94 0.93 0.59
2450.377 7.10 1.06 0.81 3138.502 7.06 1.05 0.79
2454.428 6.54 0.75 0.52 3224.270 6.74 0.88 0.63
2455.403 6.74 0.83 0.59 3483.548 6.59 0.74 0.59
2460.350 7.34 1.13 0.89 3489.497 7.27 1.08 0.85
2473.319 7.00 1.00 0.72
Observations in 1967
J.D.hel. DeltaV Delta(b-v) Delta(u-b) J.D.hel. DeltaV Delta(b-v) Delta(u-b)
2430000+ 2430000+
9777.538 +0.092 0.808 0.764 9786.570 -0.268 0.636 0.564
9780.604 -0.552 0.568 0.477 9796.555 -0.520 0.575 0.504
9781.533 -0.572 0.580 0.492 9812.594 -0.492 0.590 0.499
9782.521 -0.345 0.688 0.586 9819.575 -0.720 0.504 0.403
9783.557 -0.170 0.788 9825.617 -0.006 0.747 0.733
9784.574 +0.026 0.818 0.817
RZ Geminorum
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2369.576 10.21 1.23 2448.469 10.45 1.20
2404.473 10.37 1.17 2450.392 9.69 1.06
2429.433 10.04 1.19 2453.428 10.35 1.25
2443.463 10.15 1.05 2455.424 9.61 0.90
Table 3 (cont.)
(RZ Gem)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2460.379 9.58 0.90 3219.310 9.82 1.09,
2473.300 9.89 1.14: 3227.274 10.28: 1.26:
2714.551 9.88 0.94 3483.515 9.49 0.86
2715.612 9.68 0.95 3490.482 9.93 1.10
2756.399 10.15 1.21 3598.305 10.49: 1.19:
2816.320 10.05 1.14
BB Herculis
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2202.506 10.18 1.19 2640.330 10.40: 0.93:
2206.462 9.81 0.89 2646.323 10.40 1.25
2255.444 10.30 1.22 2927.510 9.86 0.89
2277.397 10.21 1.10 2949.374 9.79 0.89
2471.611 10.02 1.07 3304.426 9.95 1.00
2522.526 9.95 0.95 3375.471 10.36 1.18:
2543.473 10.02 0.88 3388.305 10.18 1.07
2591.385 10.01 0.95 3679.395 9.96 0.92
2620.473 9.93 0.95 3714.398 10.07 0.97
2639.326 10.44 1.14: 3722.424 9.91 0.84
X Lacertae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2365.298 8.54 1.02 0.70 2738.327 8.17 0.86 0.56
2407.297 8.28 0.96 0.54: 2939.500 8.22 0.83 0.51
2620.522 8.44 0.95 0.70 3075.353 8.23 0.82 0.56
2642.425 8.46 0.96 0.73 3337.501 8.23 0.81 0.63:
2646.418 8.22 0.91 0.54 3340.522 8.58 1.06 0.78
2675.479 8.48 1.03 0.67 3390.341 8.49 0.98 0.73
2676.449 8.53 1.04 0.72 3423.518 8.34 0.89 0.62
2685.512 8.41 0.94 0.74: 3425.267 8.27 0.90 0.63
2715.420 8.43 0.94 0.65 3438.245 8.56 1.03 0.73
2720.336 8.54 1.00 0.73
Table 3 (cont.)
(X Lac)
Observations in 1967
J.D.hel. DeltaV Delta(b-v) Delta(u-b) J.D.hel. DeltaV Delta(b-v) Delta(u-b)
2430000+ 2430000+
9720.506 -0.684 0.409 0.879 9737.455 -0.911 0.294 0.865
9724.495 -0.537 0.472 1.007 9739.514 -0.717 0.392 0.988
9726.458 -0.882 0.301 0.810 9756.601 -0.611 0.436 0.988
9727.456 -0.916 0.326 0.894 9757.317 -0.583 0.499 1.062
9731.478 -0.688 0.345 0.961 9763.562 -0.579 0.451 0.965
9732.428 -0.953 0.296 0.839 9770.327 -0.960 0.293 0.848
9733.522 -0.835 0.361 0.896 9779.588 -0.524 0.418 0.967
RR Lacertae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2289.494 8.51 0.74 0.45 2756.348 9.03 1.00 0.61
2318.452 9.17 1.10 0.70 2767.282 9.13 1.01 0.74
2407.233 8.96 0.97 2776.325* 8.54 0.78 0.48
2646.403 9.25 1.05: 0.83: 2960.401 9.15 1.12 0.78
2672.526 9.14 1.10 0.66 3045.521 8.75 0.83 0.49
2675.464 8.74 0.91 3375.452 8.86 0.95 0.59
2676.351 8.90 0.94 0.74: 3424.547 8.46 0.75 0.47
2714.350 8.80 0.93 0.55: 3425.493 8.61 0.78 0.51
2728.329* 8.99 1.03 3464.354 8.64 0.86 0.59
2738.342 8.44 0.73 0.44
BG Lacertae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2278.492 8.56 0.84 0.44: 2676.366 9.06 1.08 0.69:
2289.468 8.56 0.84 0.55: 2685.458 8.79 1.03 0.73
2297.457 9.03 1.01: 0.70: 2712.364* 8.85 1.05 0.69
2314.331 9.21: 1.03: 0.79: 2720.301 8.99 0.98 0.61
2318.408 8.97 1.09 0.68 2743.358* 8.65 0.93 0.61
2365.278 8.76 0.97 0.70 2939.423 8.63 0.89 0.50
2407.193 8.59 0.86 0.55 2960.483 8.83 0.88 0.66:
2591.444 9.14 1.06 0.80 3050.472 9.09: 1.06: 0.72:
2675.365 8.88 1.11 0.75
Table 3 (cont.)
(BG Lac)
Observations in 1967
J.D.hel. DeltaV Delta(b-v) Delta(u-b) J.D.hel. DeltaV Delta(b-v) Delta(u-b)
2430000+ 2430000+
9738.499 +0.525 0.383 0.359 9780.488 +0.381 0.344 0.401
9760.564 +0.562 0.367 0.449 9782.500 +0.236 0.238 0.144
9762.527 -0.016 0.158 0.134 9783.386 -0.114 0.142 0.111
9763.472 +0.180 0.262 0.272 9787.478 +0.514 0.365 0.367
9769.468 +0.291 0.313 0.306 9788.502 -0.080 0.119 0.046
9777.354 +0.133 0.212 0.138
CS Monocerotis
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2404.546 10.71 1.11 2454.286 11.08 1.25
2424.390* 10.71 1.07 2455.325 11.22 1.25
2429.412 11.21 1.20 2473.278 10.89 1.23
2432.440 10.86 1.20 2743.507* 11.00 1.24
2443.370 11.04 1.21 2775.472* 10.78 1.23:
2448.369 11.20 1.26 2837.289 11.02: 1.21:
2449.248 11.28 1.25 2841.267 10.79 1.12
2450.321 10.94 1.21 2869.323* 10.75 1.14
2451.319 10.71 1.12 3217.266 11.11: 1.26:
2453.343 10.93 1.20 3437.602 11.15 1.26
CV Monocerotis
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2424.424* 10.04 1.34 2743.525* 10.36 1.46:
2448.389 10.54 1.42 2775.491* 10.33 1.48:
2449.263 10.52 1.36: 2816.355 9.94 1.20
2450.341 9.98 1.15 2831.322 10.51 1.35
2453.357 10.46: 1.40: 2841.284 10.57 1.42
2454.305 10.55 1.44 2869.305* 10.23 1.37:
2455.344 10.11 1.24 3162.418 10.30 1.43
2473.290 10.13: 1.41: 3424.621 10.03 1.32:
2715.632 10.25 1.41 3483.530 9.99 1.21
Table 3 (cont.)
RS Orionis
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2404.448 8.05 0.82 0.51 2767.402 8.12 0.86 0.53
2443.428 8.21 0.92 0.55 2816.336 8.55 1.05 0.77
2448.454 8.75 1.10 0.74 2837.304 8.26 0.95 0.66
2450.362 8.08 0.82 0.53 2850.295 8.33 0.93 0.58
2453.413 8.61 1.11 0.75 3140.373 8.27 0.99 0.54
2455.379 8.86 1.18 0.85 3209.281 8.37 0.97 0.60
2460.364 8.45 1.04 0.76: 3214.317 8.02 0.81 0.50
2467.314 8.24: 1.01: 0.58: 3219.295 8.79: 1.19: 0.82:
2471.334 8.66 1.08 0.61 3226.284 8.56 1.05 0.58
2473.417 8.17 0.90 0.52 3483.637 8.76 1.20 0.90:
2522.306 8.72 1.19 0.75 3560.402 8.86 1.16 0.95:
2756.515 8.65 1.13 0.73
GQ Orionis
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2404.426 8.74 0.90 0.67 2777.476* 9.16 1.20 0.88
2424.437* 9.19 1.17 0.94 2794.386 9.16 1.12
2448.411 8.95 1.06 0.72 2816.371 8.71 0.89 0.62
2451.335 9.27 1.18 0.74: 2831.271 9.13 1.05 0.68
2453.378 8.70 0.81 0.61 2841.301 8.65 0.81 0.61
2454.329 8.66 0.85 0.62 2850.262 8.69 0.85 0.60
2460.397 9.30: 1.04: 0.90: 2869.342* 8.74 0.91
2711.619* 8.73 0.90 0.65 3124.553 9.00 0.99 0.59:
2743.569* 9.27 1.22 0.73: 3228.274 8.90 0.87 0.69
2756.489 8.76 0.90 0.74 3437.591 8.80 0.94 0.75
2767.529 8.96 1.03: 3490.421 8.82 0.98 0.88:
2776.455* 9.01 1.14 0.76
AW Persei
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2404.520 7.52 1.08 0.59 2424.370* 7.12 0.95
Table 3 (cont.)
(AW Per)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2434.301 7.27 1.03 0.61 2743.469* 7.37 1.12 0.79:
2448.432 7.81 1.21 0.79 2756.377 7.36 1.18: 0.70:
2451.352 7.22 0.98 0.65 2767.361 7.06 0.91 0.66
2453.397 7.56 1.19 0.75 2777.317* 7.70 1.23 0.85:
2454.345 7.77 1.25 0.75 2829.336 7.74 1.23 0.83
2455.361 7.84 1.22 0.74 2831.286 7.39 1.01 0.65
2460.332 7.66 1.21 0.76 2837.271 7.67 1.13 0.79:
2465.252 7.40 1.10 0.68 2869.283* 7.82 1.18 0.77
2471.317 7.36 1.04 0.68 2871.278 7.16 1.00 0.58
2685.584 7.43 1.16 0.65: 3426.457 7.06 0.92 0.51:
2711.631* 7.46 1.15 0.77
HR 690
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
3162.361 6.26 0.90 0.52: 3489.357 6.23 0.87 0.68
3178.234 6.29 0.87 0.56 3546.260 6.25 0.88 0.63
3202.294 6.26 0.79: 0.64: 3560.283 6.20 0.86 0.60
3385.549 6.18 0.84 0.67 3737.465 6.30 0.86 0.62
3420.487 6.31 0.88 0.66 3777.394 6.22 0.82 0.72
3424.448 6.24 0.85 3788.540 6.22 0.85 0.63
3425.472 6.25 0.90 0.63 3789.391 6.28 0.85 0.56
3437.417 6.22 0.85 0.56 3803.313 6.26 0.83 0.68
3483.346 6.22 0.84 0.64 3830.263 6.22 0.86 0.71
S Sagittae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2289.398 5.84 0.98 0.82: 2620.433 5.32 0.63 0.42
2297.406 5.79 0.98 0.72 2622.521 5.44 0.75 0.47
2343.276 5.33 0.61 0.39 2623.494 5.67 0.91 0.64
2543.570 5.65 0.82 0.49 2635.329 5.85 0.85 0.58
2591.468 5.89 1.00 0.80 2642.356 5.97 1.03 0.80
2613.428 5.38 0.75 0.41 2646.337 5.43 0.77 0.43
Table 3 (cont.)
(S Sge)
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2673.362 5.56 0.91: 0.56: 3351.505 5.39 0.72 0.50
2676.324 6.02 1.01 0.76 3403.404 5.76 0.90 0.72
2904.508 5.45 0.69 0.39 3724.500 5.97 0.97 0.70
2948.470 5.41 0.74 0.45 3743.299 5.35: 0.62: 0.35:
Observations in 1953
J.D.hel. Deltav Delta(b-v) J.D.hel. DeltaV Delta(b-v)
2430000+ 2430000+
4584.510 +0.115 1.068 4623.463 -0.173 0.691
4585.517 +0.357 1.273 4624.486 -0.055 0.761
4590.550 -0.192 0.876 4627.483 +0.240 1.026
4597.522 +0.139 0.941 4628.482 +0.451 1.127
4622.450 +0.211 0.940 4630.401 +0.370 1.015
U Vulpeculae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2202.531 7.26: 1.45: 1.20: 2543.499 6.90 1.26 0.96
2206.483 6.81 1.15 0.80 2589.420 7.03 1.25 0.89
2229.506 7.19 1.33 0.94 2601.535 7.28 1.38 1.16
2289.420 7.15 1.36 0.98 2622.375 6.79 1.14 0.87
2307.406 7.44 1.51 1.20 2640.346 6.96 1.32 0.85:
2308.334 7.42 1.51 1.16 2645.449 6.99 1.22 0.82
2343.244 6.85 1.21 0.90 2871.580 6.93 1.28 0.98
2522.549 7.32: 1.55: 1.20: 2928.404 7.05 1.33 0.93
2523.522 7.50 1.44: 2939.407 7.48 1.44
2532.552 7.36 1.44 1.09 2948.457 7.27 1.32 0.98
Observations in 1953
J.D.hel. DeltaV Delta(b-v) J.D.hel. DeltaV Delta(b-v)
2430000+ 2430000+
4584.468 0.447 0.186 4597.482 1.052 0.398
4585.456 0.479 0.267 4598.443 0.737 0.264
4590.513 0.709 0.292
Table 3 (cont.)
X Vulpeculae
J.D.hel. V B-V U-B J.D.hel. V B-V U-B
2440000+ 2440000+
2202.473 9.18 1.61 1.11 2646.433 8.71 1.33 0.94
2206.441 8.81 1.48 1.07 2666.310 8.49 1.33 1.05
2266.369 9.16 1.61 1.13 2669.356 9.08 1.63 1.22
2289.444 8.88: 1.53: 1.24: 2673.346 8.65 1.39 1.12
2471.633 8.80 1.42 1.08 2675.326 9.02 1.55 1.05:
2532.534 8.78 1.38 1.07 2949.389 8.91 1.44
2563.548 9.17 1.41: 1.19: 2960.450 9.12 1.60 1.35:
2591.402 8.70 1.39 1.15 2990.386 8.83 1.50 1.00:
2622.533 8.55 1.37 0.99 3363.474 8.90 1.53 1.24
2639.343 9.16 1.50: 1.16: 3386.372 8.52: 1.26: 1.02:
2640.400 8.47 1.28 1.01
listed in Table 3 using the actual periods available after constructing the O-C
diagrams. The value of the actual period is indicated for each light curve. It is the B
light curve that is shown in the figures instead of the V one because the determination of
the normal maxima was made with the help of the B light curves.
The method of using the other published observational data in constructing the O-C
diagrams is the same as described in Paper I (p. 32). The O-C values determined on the basis
of visual, photographic and photoelectric observations are marked with open circles, filled
circles and triangles, respectively. The size of these marks denotes the weight of the O-C
values to be found in the figures of this section.
The columns in the tables of the O-C residuals for each variable contain the
following data:
1. The moment of normal maximum (or that of median brightness) 2. The corresponding epoch
3. The O-C residual in days
4. The type of observation (vis for visual, pg for photographic and pe for photoelectric
observations)
5. The weight of the O-C residual depending on the type, number and quality of the
observations
6. The source of the observational data. When the name of the observer is not identical
with the name (or one of the names) given in the reference the observer's name is indicated
in the footnote to the table.
The determination of the O-C curves was by a weighted least squares fitting
procedure. The O-C residuals with zero weight are not plotted in the diagrams, those with
0.5 weight are plotted but were usually omitted in the curve fitting procedure (otherwise
the use of the O-C residuals with 0.5 weight is indicated in the remarks relating to the
given variable).
The formula by which the O-C residuals have been calculated is indicated at each
variable. These formulae usually refer to maximum light. If O-C diagrams for both maximum
and median brightnesses are presented, the two different calculated ephemerides are marked
with C_{max} and C_{med}, respectively. O-C diagrams for the median brightness are
published here only if they are fairly complete.
V 386 Cygni
The light and colour curves of this Cepheid which has a blue
Figure 2 B and B-V curves of V 386 Cyg photometric companion of spectral type B9 (Madore 1977) are shown in Fig. 2. The available observational material is not too rich. This is the reason for also using the 0.5 weight points in determining the correct value of the period. The O-C residuals have been computed by the formula: C = 2442777.118 + 5.257606d*E The period of this Cepheid has remained constant since the discovery of its light variation (see Fig. 3). Table 3 O-C residuals for V 386 Cyg Obs.Max.J.D. E O-C Type w Reference 2416347.178 -5027 +0.045d pg 0.5 Parenago (1940) 2427977.09 -2815 +0.13 vis 0.5 Selivanov (1936) 2428045.352 -2802 +0.046 vis 0.5 Szafraniec^1 (1961) 2428555.275 -2705 -0.019 pg 0.5 Parenago (1940) 2429144.169 -2593 +0.023 pg 0.5 Ishchenko (1948) 2429454.348 -2534 +0.004 pg 0.5 Ishchenko (1948) 2429827.585 -2463 -0.049 pg 0.5 Ishchenko (1948) 2434149.248 -1641 -0.139 pg 1 Shteiman (1958) 2435689.768 -1348 -0.097 pg 1 Shteiman (1958) 2436094.879 -1271 +0.178 pg 0.5 Korovkina (1958) 2436762.403 -1144 -0.014 pe 3 Weaver et al. (1960) 2436804.456 -1136 -0.022 pe 3 Oosterhoff (1960) 2437251.385 -1051 +0.011 pe 2 Mitchell et al. (1964) 2438224.025 -866 -0.006 pg 1 Dultsev (1967) 2442777.160 0 +0.042 pe 3 present paper Remark: 1 Observer: Piegza
Figure 3 O-C diagram of V 386 Cyg BG Lacertae There is a faint NW companion within the edge of the diaphragm. The present amplitudes in B and U bands are smaller than those given by Schaltenbrand and Tammann (1971), which can be attributed to the effect of this optical companion (see Fig. 4). According to Madore (1977) BG Lac has a B8 type photometric companion. This physical companion is obviously not identical with the optical companion star. The O-C residuals plotted in Fig. 5 have been computed with the formula: C = 2442673.222 + 5.331932d*E
Figure 4 B, B-V and U-B curves of BG Lac
Figure 5 O-C diagram of BG Lac The O-C diagram can be approximated by a straight line which shows the constancy of the period. Table 5 O-C residuals for BG Lac Obs.Max.J.D. E O-C Type Reference 2414899.7 -5209 +0.5d pg 0 Parenago (1934a) 2415256.1 -5142 -0.3 p9 0 Parenago (1934a) 2415613.6 -5075 -0.1 pg 0.5 Parenago (1934a) 2416024.2 -4998 0.0 pg 0.5 Parenago (1934a) 2417469.3 -4727 +0.1 pg 0.5 Parenago (1934a) 2417826.5 -4660 +0.1 pg 0.5 Parenago (1934a) 2420455.051 -4167 -0.010 pg 0.5 Robinson (1933) 2425850.928 -3155 -0.049 p9 1 Wachmann (1935) 2426192.223 -3091 +0.003 p9 1 Wachmann (1935) Table 5 (cont.) Obs.Max.J.D. E O-C Type w Reference 2426560.056 -3022 -0.068d pg 1 Wachmann (1935) 2426928.005 -2953 -0.022 pg 1 Wachmann (1935) 2427258.761 -2891 +0.154 vis 0.5 Iwanowska et al. (1938) 2427295.998 -2884 +0.068 vis 1 Florya et al. (1953) 2427333.241 -2877 -0.013 pg 1 Gesundheit (1938) 2427695.773 -2809 -0.052 pg 1 Gesundheit (1938) 2427727.949 -2803 +0.132 vis 0.5 Iwanowska et al. (1938) 2428826.250 -2597 +0.055 pg 1 Ishchenko (1948) 2429114.135 -2543 +0.016 pg 1 Ishchenko (1948) 2429439.435 -2482 +0.068 pg 1 Ishchenko (1948) 2429844.602 -2406 +0.008 pg 1 Ishchenko (1948) 2433129.068 -1790 +0.004 pe 3 Eggen (1951) 2435389.791 -1366 -0.012 pg 1 Mashnauskas (1960) 2435938.962 -1263 -0.030 pe 3 Bahner et al. (1977) 2436834.834 -1095 +0.078 pe 2 Bahner et al. (1962) 2437261.307 -1015 -0.004 pe 3 Mitchell et al. (1964) 2439772.614 -544 -0.037 pe 3 present paper^1 2442673.231 0 +0.009 pe 3 present paper Remark: 1 Observer: Abaffy delta Cephei
Figure 6 B, B-V and U-B curves of delta Cep
This star is one of the most frequently observed Cepheid variables. Its light and colour
curves are plotted in Fig. 6. The large number of the photoelectric observational series
made it possible to construct the O-C diagram not only for the maximum brightness but also
for the median brightness.
The O-C residuals for this star have been obtained by the formulae:
C_{max} = 2442756.490 + 5.366270d*E ,
C_{med} = 2442755.850 + 5.366270d*E .
Although several sudden period changes have been reported (e.g. Kukarkin et al. 1969-1970)
the O-C diagram in Fig. 7 can be approximated by a parabolic curve better than by three (or
more)
Figure 7 O-C diagram of delta Cep
straight lines. The equation of the parabolic curve for the maximum brightness is as follows:
C_{par} = 2442756.490 + 5.366270d*E - 7.6*10^{-9}*E^2
Table 6 O-C residuals for delta Cep
(maximum brightness)
Obs.Max.J.D. E O-C Type w Reference
2373090.249 -12982 -1.324d vis 1 Goodricke (1786)
2373101.003 -12980 -1.302 vis 1 Goodricke^1 (1786)
Pigott (1786)
2375870.126 -12464 -1.175 vis 1 Nielsen^2 (1933)
2384874.9 -10786 -1.0 vis 0.5 Muller et al.^3 (1918-1920)
2385105.889 -10743 -0.762 vis 1 Westphal (1817, 1818)
2387670.994 -10265 -0.734 vis 1 Muller^4 (1925)
2388862.263 -10043 -0.777 vis 1 Muller^4 (1925)
2393606.216 -9159 -0.607 vis 1 Argelander (1869)
2393842.265 -9115 -0.674 vis 1 Hagen^5 (1903)
2394008.616 -9084 -0.677 vis 1 Argelander (1869)
2394201.933 -9048 -0.546 vis 1 Hagen^5 (1903)
Table 6 (cont.)
Obs.Max.J.D. E O-C Type w Reference
2394389.669 -9013 -0.629d vis 1 Argelander (1869)
2394711.741 -8953 -0.534 vis 1 Argelander (1869)
2394958.528 -8907 -0.595 vis 1 Hagen^5 (1903)
2395173.145 -8867 -0.629 vis 1 Argelander (1869)
2395258.781 -8851 -0.853 vis 0.5 Schmidt (1857b)
2395522.016 -8802 -0.565 vis 1 Argelander (1869)
2395752.752 -8759 -0.579 vis 1 Hagen^5 (1903)
2395860.058 -8739 -0.598 vis 1 Argelander (1869)
2396235.803 -8669 -0.492 vis 1 Argelander (1869)
2396240.757 -8668 -0.905 vis 0.5 Schmidt (1857b)
2396241.068 -8668 -0.594 vis 1 Hagen^5 (1903)
2396611.115 -8599 -0.819 vis 0.5 Schmidt (1857b)
2396729.378 -8577 -0.614 vis 1 Hagen^5 (1903)
2397287.837 -8473 -0.247 vis 0 Hagen^5 (1903)
2397319.799 -8467 -0.483 vis 1 Argelander (1869)
2397400.321 -8452 -0.455 vis 1 Johnson (1853)
2397690.007 -8398 -0.548 vis 1 Argelander (1869)
2397738.331 -8389 -0.520 vis 1 Hagen^5 (1903)
2398248.058 -8294 -0.589 vis 1 Hagen^5 (1903)
2398328.628 -8279 -0.513 vis 1 Argelander (1869)
2398763.398 -8198 -0.411 vis 1 Argelander (1869)
2398800.942 -8191 -0.430 vis 0.5 Schonfeld (1861)
2398848.890 -8182 -0.779 vis 0.5 Schmidt (1857b)
2398999.378 -8154 -0.546 vis 1 Hagen^5 (1903)
2399171.144 -8122 -0.501 vis 1 Argelander (1869)
2399197.960 -8117 -0.516 vis 0.5 Schonfeld (1861)
2399455.415 -8069 -0.642 vis 0.5 Schmidt (1858a)
2399487.769 -8063 -0.486 vis 0.5 Schonfeld (1861)
2399509.180 -8059 -0.540 vis 1 Argelander (1869)
2399589.627 -8044 -0.587 vis 1 Zinner et al.^6 (1931)
2399739.997 -8016 -0.473 vis 1 Muller^4 (1925)
2399841.969 -7997 -0.460 vis 1 Argelander (1869)
2399852.250 -7995 -0.911 vis 0.5 Schmidt (1859)
2399976.139 -7972 -0.447 vis 0.5 Auwers (1859)
2400088.858 -7951 -0.419 vis 1 Hagen^5 (1903)
2400180.032 -7934 -0.472 vis 1 Argelander (1869)
2400206.736 -7929 -0.599 vis 0.5 Schonfeld (1869)
2400228.275 -7925 -0.525 vis 1 Zinner et al.^6 (1931)
2400270.922 -7917 -0.808 vis 0.5 Schmidt (1860b)
2400609.023 -7854 -0.782 vis 0.5 Schmidt (1861)
2400957.910 -7789 -0.703 vis 0.5 Schmidt (1862)
2401322.843 -7721 -0.676 vis 0.5 Schmidt (1863)
2401698.433 -7651 -0.725 vis 0.5 Schmidt (1864)
2402063.387 -7583 -0.678 vis 0.5 Schmidt (1865)
2402407.160 -7519 -0.346 vis 1 Valentiner^7 (1900)
2402449.731 -7511 -0.705 vis 0.5 Schmidt (1866)
2402739.798 -7457 -0.417 vis 1 Valentiner^7 (1900)
2402803.996 -7445 -0.614 vis 0.5 Schmidt (1867)
2403110.059 -7388 -0.428 vis 1 Valentiner^7 (1900)
2403152.700 -7380 -0.717 vis 0.5 Schmidt (1868)
2403458.716 -7323 -0.579 vis 1 Valentiner^7 (1900)
2403533.775 -7309 -0.648 vis 0.5 Schmidt (1869)
2403539.356 -7308 -0.433 vis 1 Zinner et al.^6 (1931)
2403871.758 -7246 -0.740 vis 0.5 Schmidt (1870)
2403893.411 -7242 -0.552 vis 1 Valentiner^7 (1900)
Table 6 (cont.)
Obs.Max.J.D. E O-C Type w Reference
2404242.293 -7177 -0.477d vis 1 Valentiner^7 (1900)
2404268.974 -7172 -0.628 vis 0.5 Schmidt (1871)
2404392.631 -7149 -0.395 vis 1 Zinner et al.^6 (1931)
2404601.859 -7110 -0.451 vis 1 Valentiner^7 (1900)
2404628.487 -7105 -0.655 vis 0.5 Schmidt (1872)
2404998.802 -7036 -0.612 vis 0.5 Schmidt (1873)
2405020.493 -7032 -0.386 vis 1 Valentiner^7 (1900)
2405352.911 -6970 -0.677 vis 0.5 Schmidt (1874)
2405417.586 -6958 -0.397 vis 1 Valentiner^7 (1900)
2405701.804 -6905 -0.592 vis 0.5 Schmidt (1875)
2405712.890 -6903 -0.238 vis 1 Valentiner^7 (1900)
2406087.955 -6833 -0.812 vis 0 Chandler (1877)
2406114.996 -6828 -0.602 vis 0.5 Schmidt (1876)
2406136.633 -6824 -0.431 vis 1 Valentiner^7 (1900)
2406372.746 -6780 -0.433 vis 1 Belyavsky^8 (1910)
2406436.939 -6768 -0.636 vis 0.5 Schmidt (1877)
2406812.658 -6698 -0.556 vis 0.5 Schmidt (1878)
2407193.609 -6627 -0.610 vis 0'.5 Schmidt (1879)
2407198.766 -6626 -0.819 vis 0 Schwab (1879)
2407499.780 -6570 -0.316 vis 1 Schur (1895)
2407563.892 -6558 -0.599 vis 0.5 Schmidt (1880)
2407907.375 -6494 -0.558 vis 0.5 Schmidt (1881)
2408277.556 -6425 -0.649 vis 0.5 Schmidt (1882)
2408412.117 -6400 -0.245 vis 1 Wilsing (1897)
2408637.187 -6358 -0.558 vis 0.5 Schmidt (1883)
2408766.269 -6334 -0.267 vis 1 Schur (1895)
2409018.272 -6287 -0.479 vis 0.5 Schmidt (1884)
2409957.650 -6112 -0.198 vis 0.5 Hagen (1891)
2410955.596 -5926 -0.378 vis 1 Valentiner^7 (1900)
2411197.178 -5881 -0.278 vis 1 Valentiner^7 (1900)
2411255.897 -5870 -0.588 vis 0.5 Yendell (1890b)
2411395.744 -5844 -0.264 vis 0.5 Porro (1896)
2411481.686 -5828 -0.182 vis 1 Valentiner^7 (1900)
2412275.908 -5680 -0.168 vis 0.5 Hertzsprung^9 (1919)
2413424.210 -5466 -0.248 vis 1 Stratonov (1904)
2413483.411 -5455 -0.076 vis 1 Plassmann (1900)
2413783.874 -5399 -0.124 vis 0.5 Hertzsprung^10 (1919)
2413789.159 -5398 -0.206 vis 1 Plassmann (1900)
2413826.659 -5391 -0.269 vis 1 Stratonov (1904)
2413832.202 -5390 -0.093 vis 1 Pickering (1904)
2413918.031 -5374 -0.124 vis 0.5 Belyavsky (1904)
2413950.090 -5368 -0.263 vis 0.5 Nijland (1923)
2414111.171 -5338 -0.170 vis 1 Plassmann (1900)
2414170.120 -5327 -0.250 vis 1 Stratonov (1904)
2414513.534 -5263 -0.277 vis 1 Plassmann (1900)
2414551.158 -5256 -0.217 vis 1 Stebbins (1908)
2414556.556 -5255 -0.185 vis 1 Luizet (1912)
2414615.484 -5244 -0.286 vis 0.5 Zinner^11 (1932)
2414782.125 -5213 +0.001 vis 0.5 Belyavsky (1904)
2414873.181 -5196 -0.170 vis 1 Luizet (1912)
2414878.531 -5195 -0.186 vis 1 Plassmann (1900)
2414926.748 -5186 -0.266 pg 1 Wirtz (1901)
2415243.464 -5127 -0.160 vis 1 Luizet (1912)
2415307.747 -5115 -0.272 vis 1 Plassmann (1901)
2415560.003 -5068 -0.231 vis 0.5 Belyavsky (1904)
Table 6 (cont.)
Obs.Max.J.D. E O-C Type w Reference
2415608.375 -5059 -0.155d vis 1 Plassmann (1906)
2415640.568 -5053 -0.160 vis 1 Luizet (1912)
2415930.377 -4999 -0.129 vis 1 Plassmann (1906)
2415989.364 -4988 -0.171 vis 1 Bilt (1924b)
2415994.773 -4987 -0.129 vis 1 Luizet (1912)
2416032.294 -4980 -0.171 vis 0.5 Roy et al. (1905)
2416085.679 -4970 -0.449 vis 0.5 Lau (1903)
2416305.935 -4929 -0.210 vis 1 Plassmann (1906)
2416370.401 -4917 -0.139 vis 1 Luizet (1912)
2416622.474 -4870 -0.281 vis 0.5 Götz (1906)
2416676.288 -4860 -0.130 vis 1 Plassmann (1906)
2416692.311 -4857 -0.206 vis 0.5 Terkán (1905)
2416703.028 -4855 -0.221 vis 1 Bilt (1924b)
2416762.133 -4844 -0.145 vis 1 Luizet (1912)
2416799.644 -4837 -0.198 vis 0.5 Nijland (1923)
2416858.625 -4826 -0.246 vis 1 Tass^12 (1925)
2416912.417 -4816 -0.117 vis 0.5 Schiller (1906)
2416998.171 -4800 -0.223 vis 0.5 Zinner^11 (1932)
2417035.634 -4793 -0.324 vis 1 Plassmann (1906)
2417073.335 -4786 -0.187 pg 1 Meyermann (1907)
2417111.036 -4779 -0.050 vis 1 Luizet (1912)
2417169.937 -4768 -0.178 vis 1 Bilt (1924b)
2417196.860 -4763 -0.086 vis 0.5 Furness^13 (1913)
2417255.729 -4752 -0.246 vis 0.5 Lohnert (1909)
2417336.251 -4737 -0.218 vis 1 Nijland (1923)
2417390.011 -4727 -0.121 vis 1 Plassmann (1906, 1908)
2417481.212 -4710 -0.146 vis 1 Luizet (1912)
2417701.232 -4669 -0.143 pg 1 Jordan (1919)
2417744.061 -4661 -0.245 vis 1 Bilt (1924b)
2417776.361 -4655 -0.142 vis 0.5 Zinner^11 (1932)
2417792.470 -4652 -0.132 vis 1 Plassmann (1908)
2417846.134 -4642 -0.131 vis 1 Luizet (1912)
2418125.055 -4590 -0.256 vis 0.5 Scheller (1912)
2418216.390 -4573 -0.147 vis 1 Luizet (1912)
2418291.535 -4559 -0.130 vis 0.5 Favaro (1909)
2418517.109 -4517 +0.061 vis 0.5 Mundler (1911)
2418586.700 -4504 -0.110 vis 1 Luizet (1912)
2418629.620 -4496 -0.120 vis 1 Bemporad (1910)
2418661.769 -4490 -0.169 vis 0.5 Scheller (1912), Kaiser (1915)
2418661.882 -4490 -0.056 vis 0.5 Olivier (1952)
2418956.993 -4435 -0.090 vis 1 Luizet (1912)
2418983.728 -4430 -0.186 vis 0.5 Padova (1911, 1912)
2419075.037 -4413 -0.103 vis 1 Bemporad (1916)
2419230.769 -4384 +0.007 vis 0.5 Hornig (1915)
2419294.847 -4372 -0.311 vis 0.5 Lau (1913)
2419380.800 -4356 -0.218 vis 0.5 Zinner^11 (1932)
2419685.646 -4299 -1.249 vis 0 Breson (1913)
2419858.581 -4267 -0.035 vis 0.5 Olivier (1952)
2420320.098 -4181 -0.017 vis 0.5 Lazzarino (1915)
2420346.859 -4176 -0.087 vis 1 Bemporad (1915)
2420379.047 -4170 -0.097 vis 0.5 Zinner^11 (1932)
2420722.611 -4106 +0.026 vis 0.5 Olivier (1952)
2420910.17 -4071 -0.23 vis 0.5 Vogelenzang (1921)
2420980.007 -4058 -0.159 vis 0.5 Luyten (1922)
2421001.382 -4054 -0.249 pg 0.5 Robinson (1933)
Table 6 (cont.)
Obs.Max.J.D. E O-C Type w Reference
2421237.822 -4010 +0.075d vis 0.5 Paci (1918)
2421430.903 -3974 -0.030 vis 0.5 Zinner^11 (1932)
2421457.714 -3969 -0.050 vis 0.5 Luyten (1922)
2421559.551 -3950 -0.173 pe 3 Guthnick (1919)
2421940.673 -3879 -0.056 vis 0.5 Luyten (1922)
2422241.065 -3823 -0.175 pe 3 Guthnick (1923)
2422278.640 -3816 -0.164 vis 0.5 Olivier (1952)
2422852.978 -3709 -0.017 vis 0.5 Zinner^11 (1932)
2422895.866 -3701 -0.059 vis 1 Nielsen (1926)
2423223.218 -3640 -0.049 vis 1 Zverev (1936)
2423335.809 -3619 -0.150 vis 1 Nielsen (1926)
2423620.263 -3566 -0.108 vis 0.5 Parenago (1938a)
2423646.971 -3561 -0.232 pg 1 Henroteau (1924)
2423679.314 -3555 -0.086 vis 0.5 Hopmann (1926)
2423829.432 -3527 -0.224 pe 2 Danjon (1927)
2423904.733 -3513 -0.050 pe 1 Pettit et al. (1933)
2424291.029 -3441 -0.126 pe 2 Danjon (1928)
2424741.882 -3357 -0.040 vis 0.5 Parenago (1938a)
2424774.021 -3351 -0.098 vis 0.5 Kukarkin (1940)
2425235.510 -3265 -0.108 vis 1 Collmann (1930)
2425401.937 -3234 -0.036 vis 1 McLaughlin (1934a)
2425418.030 -3231 -0.042 vis 0.5 Kukarkin (1940)
2425707.813 -3177 -0.037 vis 1 Parenago (1938a)
2425798.842 -3160 -0.235 vis 0.5 Fesenkov (1930)
2425852.704 -3150 -0.036 vis 1 Zverev (1936)
2425965.467 -3129 +0.036 vis 1 McLaughlin (1934a)
2426297.842 -3067 -0.298 pg 0.5 Farnsworth (1933)
2426362.410 -3055 -0.125 vis 0.5 Kukarkin (1940)
2426421.584 -3044 +0.020 vis 0.5 Parenago (1938a)
2426464.461 -3036 -0.033 vis 1 McLaughlin (1934a)
2426507.295 -3028 -0.129 vis 1 Lipinski (1934)
2426888.424 -2957 -0.006 vis 1 Florya et al. (1953)
2426920.616 -2951 -0.011 vis 1 McLaughlin (1934a)
2427221.046 -2895 -0.092 pg 2 Wesselink (1946)
2427301.584 -2880 -0.048 vis 1 Florya et al. (1953)
2427371.242 -2867 -0.152 pe 2 Smart (1935)
2427687.939 -2808 -0.065 vis 1 Florya (1938)
2427843.563 -2779 -0.063 pg 2 Wesselink (1946)
2428031.438 -2744 -0.007 vis 0.5 Parenago (1938a)
2428079.73 -2735 -0.01 vis 0.5 Sures (1937)
2428412.368 -2673 -0.082 pg 2 Wesselink (1946)
2430226.213 -2335 -0.037 pg 1 Wesselink (1946)
2430553.527 -2274 -0.065 pe 3 Stebbins (1945)
2430950.696 -2200 0.000 pe 1 Canavaggia (1949)
2432453.239 -1920 -0.013 vis 1 Petrov (1949)
2432823.4 -1851 -0.1 vis 0.5 Pohl (1951)
2433134.784 -1793 +0.016 pe 3 Eggen (1951)
2433215.36 -1778 +0.10 vis 0.5 Pohl^14 (1951)
2433403.20 -1743 +0.12 vis 0.5 Domke and Pohl^14 (1952)
2433430.00 -1738 +0.09 vis 0.5 Domke and Pohl^15 (1952)
2434476.81 -1543 +0.48 vis 0 Pohl^16 (1955)
2435045.25 -1437 +0.09 vis 0.5 Rudolph^17 (1959)
2435694.56 -1316 +0.08 vis 0.5 Rudolph^18 (1959)
2435715.894 -1312 -0.050 pe 3 Sentsova (1957)
2435978.72 -1263 -0.17 vis 0.5 Rudolph (1959)
Table 6 (cont.)
Obs.Max.J.D. E O-C Type w Reference
2436005.75 -1258 +0.03d vis 0.5 Rudolph^18 (1959)
2436139.92 -1233 +0.04 vis 0.5 Rudolph (1959)
2436172.119 -1227 +0.042 pe 2 Oke (1961b)
2436816.2 -1107 +0.2 vis 0.5 Braune et al.^17 (1962)
2436837.497 -1103 +0.003 pe 3 Bahner et al. (1962)
2437025.361 -1068 +0.047 vis 0.5 Azarnova (1962)
2437239.956 -1028 -0.008 pe 3 Mitchell et al. (1964)
2437379.58 -1002 +0.09 vis 0.5 Braune et al.^18 (1967)
2437391.06 -1000 +0.84 vis 0 Braune et al.^19 (1967)
2437937.634 -898 +0.054 pe 1 Williams (1966)
2438055.806 -876 +0.169 vis 0.5 Mayall^20 (1972)
2438232.804 -843 +0.080 vis 0.5 Mayall^21 (1972)
2438930.327 -713 -0.012 pe 3 Wisniewski et al. (1968)
2438968.05 -706 +0.15 vis 0.5 Braune et al. (1967)
2439805.040 -550 -0.002 pe 3 present paper^22
2440111.0 -493 +0.1 vis 0.5 Braune et al.^23 (1970)
2440470.60 -426 +0.14 vis 0.5 Busch (1977b)
2440475.80 -425 -0.02 vis 0.5 Braune et al.^23 (1972)
2440878.298 -350 +0.003 pe 2 Evans (1976)
2440894.35 -347 -0.04 vis 0.5 Braune et al.^23 (1972)
2441173.31 -295 -0.13 vis 0.5 Braune et al.^24 (1972)
2442058.989 -130 +0.114 vis 0.5 Mosch et al. (1976)
2442686.781 -13 +0.053 vis 0.5 Mosch et al. (1976)
2442756.458 0 -0.032 pe 3 present paper
2443035.679 +52 +0.143 vis 0.5 Busch^25 (1977a)
2443041.003 +53 +0.101 vis 0.5 Busch^26 (1977a)
2443062.286 +57 -0.081 vis 0.5 Busch^27 (1977a)
Remarks: (observers) 1 Pigott; 2 Rittenhouse; 3 Gauss;
4 Schwerd; 5 Heis; 6 Winnecke; 7 Schonfeld; 8 Glasenapp;
9 Knopf; 10 Pannekoek; 11 Hartwig; 12 Terkán; 13 Whitney;
14 Sofronijevitsch; 15 Born; 16 Munster; 77 Pohl; 18 Masuch;
19 Fernandes; 20 Ross; 21 Baldwin; 22 Abaffy; 23 Eckert;
24 Bauer; 25 Bransk; 26 Reichenbucher; 27 Enskonatus.
Table 7 O-C residuals for delta Cep
(median brightness)
Obs.Med.J.D. E O-C Type w Reference
2414550.530 -5256 -0.205d vis 1 Stebbins (1908)
2414926.104 -5186 -0.270 pg 1 Wirtz (1901)
2417335.618 -4737 -0.211 vis 1 Nijland (1923)
2421558.955 -3950 -0.129 pe 3 Guthnick (1919)
2422240.480 -3823 -0.120 pe 3 Guthnick (1923)
2424290.439 -3441 -0.076 pe 2 Danjon (1928)
2427220.466 -2895 -0.032 pg 2 Wesselink (1946)
2427370.620 -2867 -0.134 pe 2 Smart (1935)
2427842.962 -2779 -0.024 pg 2 Wesselink (1946)
2428411.735 -2673 -0.075 pg 2 Wesselink (1946)
2430552.916 -2274 -0.036 pe 3 Stebbins (1945)
2436171.529 -1227 +0.092 pe 2 Oke (1961b)
2437239.339 -1028 +0.017 pe 3 Mitchell et al. (1964)
2438929.715 -713 +0.016 pe 3 Wisniewski et al. (1968)
2442755.798 0 -0.052 pe 3 present paper
CV Monocerotis
This faint Cepheid has five very faint companions. Earlier CV Mon was thought to be
a cluster member (Arp 1960). Under the influence of these surrounding stars the V and B-V
amplitudes derived from the present photometry (see Fig. 8) are smaller than those given by
Schaltenbrand and Tammann (1971). CV Mon has a physical companion with a spectral type of
B7 (Madore 1977). It cannot be excluded that this B7 companion is the closest star among
the visible companions but none of the photometries have so far been able to separate its
photometric influence.
Figure 8 B and B-V curves of CV Mon
Figure 9 O-C diagram of CV Mon The O-C residuals given in Table 8 were computed using the formula: C = 2442773.136 + 5.378898d*E The O-C diagram in Fig 9. can be approximated by two almost parallel straight lines representing the phenomenon of the rejumping period (or stepwise O-C diagram). For CV Mon the jump and the subsequent rejump in the period occurred so suddenly that the intermediate period cannot be determined. The values of the period are: before J.D. 2436000 P = 5.378782d , after J.D. 2436000 P = 5.378898d . Table 8 O-C residuals for CV Mon Obs.Max.J.D. E O-C Type w Reference 2429364.063 -2493 +0.520d pg 0.5 Wachmann (1964b) 2429638.41 -2442 +0.54 pg 0.5 Ahnert (1947) 2429805.142 -2411 +0.529 pg 1 Teplitskaya (1951) 2430289.20 -2321 +0.49 pg 0.5 Ahnert (1947) 2430698.081 -2245 +0.571 pg 0.5 Wachmann (1964b) 2430735.80 -2238 +0.64 pg 0.5 Ahnert (1947) 2430778.688 -2230 +0.495 pg 1 Teplitskaya (1951) 2431876.114 -2026 +0.625 pg 0.5 Wachmann (1964b) 2431908.261 -2020 +0.499 pg 1 Filatov (1961) 2433005.559 -1816 +0.502 pg 0.5 Wachmann (1964b) 2434086.634 -1615 +0.418 pg 0.5 Wachmann (1964b) 2435119.417 -1423 +0.453 pg 0.5 Wachmann (1964b) 2435447.480 -1362 +0.403 pg 1 Filatov (1961) 2436571.256 -1153 -0.011 pe 2 Arp (1960) 2436630.860 -1142 +0.426 pg 0.5 Wachmann (1964b) 2441035.777 -323 +0.025 pe 3 Pel (1976) 2442773.160 0 +0.024 pe 3 present paper 2442837.641 +12 -0.042 pe 3 Turner (1978) SW Cassiopeiae
Figure 10 B and B-V curves of SW Cas
The light and colour curves of this variable are plotted in Fig. 10. The O-C
diagrams are constructed for both maximum and median brightnesses (Tables 9 and 10, Fig. 11).
The O-C residuals have been calculated using the formulae:
C_{max} = 2442989.590 + 5.440950d*E ,
C_{med} = 2442988.808 + 5.440950d*E .
The period has remained constant since the discovery of the light variation of SW Cas. The
lines fitted to these two O-C diagrams are parallel to each other.
Figure 11 O-C diagram of SW Cas Table 9 O-C residuals for SW Cas (maximum brightness) Obs.Max.J.D. E O-C Type w Reference 2418869.792 -4433 -O.067d vis 1 Enebo (1911) 2419403.033 -4335 -0.039 pg 0.5 Robinson (1933) 2421459.659 -3957 -0.092 pg 2 Jordan (1929) 2425415.478 -3230 +0.157 vis 1 Beyer (1930) 2425747.31 -3169 +0.09 pg 0.5 Kiehl, Hopp (1977) 2426041.129 -3115 +0.098 vis 0.5 Parenago (1938a) 2426269.45 -3073 -0.10 pg 0.5 Kiehl, Hopp (1977) 2426694.076 -2995 +0.131 vis 1 Kukarkin (1940) 2426873.58 -2962 +0.08 pg 0.5 Kiehl, Hopp (1977) 2428962.816 -2578 -0.005 pg 1 Tolmar (1940b) 2430578.733 -2281 -0.050 pg 1 Solov'yov (1954) 2430992.253 -2205 -0.042 pg 1 Solov'yov (1954) 2431498.269 -2112 -0.035 pg 1 Solov'yov (1954) 2432733.383 -1885 -0.016 pg 1 Solov'yov (1954) 2433457.203 -1752 +0.157 pg 1 Solov'yov (1954) 2436803.232 -1137 +0.002 pe 3 Weaver et al. (1960) 2436808.673 -1136 +0.002 pe 3 Oosterhoff (1960) 2436874.002 -1124 +0.040 pe 3 Bahner et al. (1962) 2437837.054 -947 +0.044 pg 2 Golovatyj (1964) 2442086.52 -166 +0.13 vis 0.5 Small (1974) 2442989.509 0 -0.081 pe 3 present paper Table 10 O-C residuals for SW Cas (median brightness) Obs.Med.J.D. E O-C Type W Reference 2421458.952 -3957 -0.017 pg 2 Jordan (1929) 2436807.737 -1136 -0.152 pe 3 Oosterhoff (1960) 2436873.257 -1124 +0.077 pe 3 Bahner et al. (1962) 2437836.358 -947 +0.130 pg 2 Golovatyj (1964) 2442988.840 0 +0.032 pe 3 present paper X Lacertae This star is a small amplitude Cepheid (type Is) but the light curve is not symmetrical (see Fig. 12). The O-C residuals
Figure 12 B, B-V and U-B curves of X Lac
have been derived using the formulae:
C_{max} = 2442738.132 + 5.444990d*E
C_{med} = 2442737.243 + 5.444990d*E
The O-C diagram in Fig. 13 shows one change in the period:
before J.D. 2429500 P = 5.444212d
after J.D. 2429500 P = 5.444990d
Grigorevski and Motrich (1973) tried to approximate the O-C diagram of X Lac by a
parabolic curve too, but one can see in Fig. 13 that the proper approximation is that using
two straight lines.
Figure 13 O-C diagram of X Lac
Table 11 O-C residuals for X Lac
(maximum brightness)
Obs.Max.J.D. E O-C Type w Reference
2417551.255 -4626 +1.647d vis 1 Seares (1906, 1907b)
2417768.734 -4586 +1.326 vis 0.5 Zeipel (1908)
2418890.652 -4380 +1.576 pg 0.5 Robinson (1933)
2419870.451 -4200 +1.277 pg 1 Martin, Plummer (1916)
2420012.124 -4174 +1.380 pg 1 Hertzsprung (1922)
2420741.644 -4040 +1.272 pg 1 Martin, Plummer (1916)
2421460.502 -3908 +1.391 pg 1 Hertzsprung (1922)
2421487.466 -3903 +1.130 pg 1 Jordan (1929)
2421737.914 -3857 +1.108 vis 0.5 Doberck (1920b)
2423458.111 -3541 +0.689 vis 1 Doberck (1924c)
2425744.43 -3121 +0.12 pg 0.5 Kiehl, Hopp (1977)
2425837.931 -3104 +1.048 vis 0 Parenago (1938a)
2426234.610 -3031 +0.243 vis 0.5 Terkán (1935)
2426539.709 -2975 +0.422 vis 1 Kukarkin (1940)
2426550.512 -2973 +0.335 pg 1 Zonn (1933)
2426757.627 -2935 +0.541 vis 0.5 Dziewulski et al. (1946)
2426801.263 -2927 +0.617 vis 0 Dziewulski et al. (1946)
2426931.54 -2903 +0.22 pg 0.5 Kiehl, Hopp (1977)
2427105.971 -2871 +0.405 pg 1 Zonn (1933)
2427296.426 -2836 +0.286 vis 0.5 Florya et al. (1953)
2428287.364 -2654 +0.235 vis 0.5 Dziewulski et al. (1946)
2428347.281 -2643 +0.258 pg 0.5 Dziewulski et al. (1946)
2428423.09 -2629 -0.16 pg 0.5 Fu De-Lian (1964)
2428565.052 -2603 +0.229 pg 0.5 Dziewulski et al. (1946)
2429049.37 -2514 -0.05 pg 0.5 Katz (1946)
2433536.080 -1690 -0.019 p9 1 Solov'yov (1952)
2434358.290 -1539 -0.002 pg 1 Romano (1955)
2435757.739 -1282 +0.084 pe 3 Bahner et al. (1971)
2436122.564 -1215 +0.095 pg 1 Makarenko (1969)
Table 11 (cont.)
Obs.Max.J.D. E O-C Type w Reference
2436193.284 -1202 +0.030d pe 3 Bahner et al. (1971)
2436487.341 -1148 +0.058 pg 1 Makarenko (1969)
2436786.788 -1093 +0.030 pe 3 Weaver et al. (1960)
2436797.646 -1091 -0.002 pe 3 Oosterhoff (1960)
2436835.700 -1084 -0.063 pe 3 Bahner et al. (1962)
2436841.134 -1083 -0.074 pg 1 Makarenko (1969)
2437200.536 -1017 -0.041 pg 1 Makarenko (1969)
2437216.833 -1014 -0.079 pe 3 Mitchell et al. (1964)
2437576.301 -948 +0.020 pg 1 Makarenko (1969)
2437635.999 -937 -0.177 pg 1 Golovatyj (1964)
2437946.440 -880 -0.101 pg 1 Makarenko (1969)
2438305.897 -814 -0.013 pg 1 Makarenko (1969)
2438866.747 -711 +0.003 pg 1 Makarenko (1969)
2439743.308 -550 -0.080 pe 3 present paper^1
2440195.346 -467 +0.024 pe 3 Asteriadis et al. (1977)
2442738.227 0 +0.095 pe 3 present paper
2443696.374 +176 -0.076 pe 2 Henden (1979)
Remark: 1 Observer: Abaffy
Table 12 O-C residuals for X Lac
(median brightness)
Obs.Med.J.D. E O-C Type w Reference
2435756.797 -1282 +0.031d pe 3 Bahner et al. (1971)
2436192.407 -1202 +0.042 pe 3 Bahner et al. (1971)
2436785.895 -1093 +0.026 pe 3 Weaver et al. (1960)
2436796.752 -1091 -0.007 pe 3 Oosterhoff (1960)
2439742.437 -550 -0.062 pe 3 present paper^1
2440194.383 -467 -0.050 pe 3 Asteriadis et al. (1977)
2442737.296 0 +0.053 pe 3 present paper
Remark: 1 Observer: Abaffy
RZ Geminorum
There is a very faint southern companion within the edge of the diaphragm. In spite
of this the V and B amplitudes are larger than reported by Schaltenbrand and Tammann (1971).
Madore (1977) pointed out that RZ Gem has a B5 photometric companion.
The O-C residuals have been computed with the formula:
C = 2442714.970 + 5.529286d*E
The O-C diagram can be approximated either by two straight lines (sudden period change), or
by a parabolic line (continuous period change). In the former case the values of the period
are:
before J.D. 2432400 P = 5.529716d ,
after J.D. 2432400 P = 5.529286d .
If a continuous period change is assumed, the equation of the approximate parabola is as follows:
C_{par} = 2442714.920 + 5.529143*E - 8.85d*10^{-8}d*E^2
Figure 14 B and B-V curves of RZ Gem Table 13 O-C residuals for RZ Gem Obs.Max.J.D. E O-C Type w Reference 2415028.54 -5007 -1.29 pg 0.5 Oosterhoff (1935) 2415791.59 -4869 -1.29 pg 0.5 Oosterhoff (1935) 2416034.80 -4825 -1.36 pg 0.5 Oosterhoff (1935) 2416460.74 -4748 -1.18 pg 0.5 Oosterhoff (1935) 2417339.82 -4589 -1.26 pg 0.5 Oosterhoff (1935) 2418291.142 -4417 -0.972 vis 0.5 Luizet (1909) 2418324.181 -4411 -1.108 vis 1 Enebo (1909) 2418351.55 -4406 -1.39 pg 0.5 Oosterhoff (1935) 2418832.935 -4319 -1.049 vis 1 Enebo (1911) 2419811.52 -4142 -1.15 pg 0.5 Oosterhoff (1935) 2420409.203 -4034 -0.627 pg 0 Robinson (1933) 2420458.75 -4025 -0.84 pg 0.5 Oosterhoff (1935) 2421277.055 -3877 -0.873 pg 1 Jordan (1929) 2421514.86 -3834 -0.83 pg 0.5. Oosterhoff (1935) 2422239.82 -3703 -0.20 pg 0 Oosterhoff (1935) 2424124.71 -3362 -0.80 pg 0.5 Oosterhoff (1935) 2424854.73 -3230 -0.65 pg 0.5 Oosterhoff (1935) 2425153.88 -3176 -0.08 pg 0 Oosterhoff (1935) 2425844.85 -3051 -0.27 pg 0.5 Oosterhoff (1935) 2426375.422 -2955 -0.508 vis 1 Kukarkin (1940) 2426712.86 -2894 -0.36 pg 0.5 Oosterhoff (1935) 2428189.08 -2627 -0.46 pg 0.5 Fu De-Lian (1964) 2428869.451 -2504 -0.187 pg 1 Koshkina (1963) Table 13 (cont.) Obs.Max.J.D. E O-C Type w Reference 2429383.624 -2411 -0.237d pg 1 Koshkina (1963) 2429632.453 -2366 -0.226 pg 1 Chudovicheva (1952) 2431556.759 -2018 -0.112 pg 1 Chudovicheva (1952) 2432557.503 -1837 -0.169 pg 1 Chudovicheva (1952) 2433530.659 -1661 -0.167 pg 0.5 Chudovicheva (1952) 2433801.844 -1612 +0.083 pg 1 Koshkina (1963) 2434304.930 -1521 +0.004 pg 1 Koshkina (1963) 2434327.082 -1517 +0.039 pg 1 Rosino, Nobili (1955) 2436831.810 -1064 0.000 pe 3 Weaver et al. (1960) 2437401.48 -961 +0.15 pg 0.5 Ahnert (1962) 2437633.563 -919 +0.007 pe 3 Mitchell et al. (1964) 2439248.161 -627 +0.053 pe 3 Takase (1969) 2442714.927 0 -0.043 pe 3 present paper
Figure 15 O-C diagram of RZ Gem V 924 Cygni Unfortunately, there are very few earlier observational data on this small amplitude Cepheid. The O-C residuals have been
Figure 16 B and B-V curves of V 924 Cyg calculated with the formula: C = 2443066.075 + 5.571472d*E The present period seems to be reliable since it is based on three photoelectric observational series but we cannot say anything certain about the behaviour of the period before J.D. 2438000. The systematically larger O-C values before this date may be caused by the earlier points in the O-C diagram (with a weight of 0.5) not being derived on the basis of published observations but rather from the published normal maxima.
Figure 17 O-C diagram of V 924 Cyg Table 14 O-C residuals for V 924 Cyg Obs.Max.J.D. E O-C Type w Reference 2432765.24 -1849 +0.82d pg 0.5 Miller, Wachmann (1961) 2434152.46 -1600 +0.74 pg 0.5 Wachmann (1976) 2434988.09 -1450 +0.65 pg 0.5 Wachmann (1976) 2435344.66 -1386 +0.65 pg 0.5 Wachmann (1976) 2436809.87 -1123 +0.56 pg 0.5 Wachmann (1976) 2438558.778 -809 +0.024 pe 2 Eggen (1969) 2441260.881 -324 -0.037 pe 3 Wachmann (1976) 2443066.098 0 +0.023 pe 3 present paper FM Cassiopeiae The light and colour curves of this Cepheid can be seen in Fig. 18. The number of reliable observational series is very small so I was obliged to take into account the O-C residuals with a weight of 0.5 (except the visual observations) when determining the value of the period. Finally, the O-C residuals have been computed with the formula: C = 2442817.713 + 5.809284d*E The period has remained constant since the discovery of the light variation of FM Cas.
Figure 18 B and B-V curves of FM Cas
Figure 19 O-C diagram of FM Cas Table 15 O-C residuals for FM Cas Obs.Max.J.D. E O-C Type w Reference 2415037.0 -4782 -0.7d pg 0 Chernova (1946) 2417065.2 -4433 0.0 pg 0.5 Chernova (1946) 2418529.2 -4181 +0.1 pg 0.5 Chernova (1946) 2426933.83 -2734 -1.30 pg 0 Kiehl, Hopp (1977) 2427812.6 -2583 +0.3 pg 0.5 Chernova (1946) 2427962.90 -2557 -0.47 pg 0 Ahnert et al. (1943) 2428393.43 -2483 +0.17 pg 0.5 Ahnert et al. (1943) 2428556.0 -2455 +0.1 pg 0.5 Chernova (1946) 2428649.08 -2439 +0.21 pg 0.5 Ahnert et al. (1943) 2429084.20 -2364 -0.37 pg 0 Ahnert et al. (1943) 2429351.59 -2318 -0.20 pg 0.5 Ahnert et al. (1943) 2429555.55 -2283 +0.43 pg 0 Ahnert et al. (1943) 2430002.50 -2206 +0.07 pg 0.5 Ahnert et al. (1943) 2430467.2 -2126 0.0 pg 0.5 Chernova^1 (1946) 2430746.273 -2078 +0.252 vis 0.5 Model, Lochel (1964) 2435108.856 -1327 +0.063 pg 0.5 Romano (1959) 2435428.047 -1272 -0.257 pg 0.5 Romano (1959) 2435654.711 -1233 -0.155 pg 0.5 Romano (1959) Table 15 (cont.) Obs.Max.J.D. E O-C Type w Reference 2435875.51 -1195 -0.11d pg 0.5 Zonn, Semeniuk (1959) 2436805.114 -1035 +0.010 pe 3 Oosterhoff (1960) 2436863.167 -1025 -0.030 pe 3 Bahner et al. (1962) 2437020.373 -998 +0.325 vis 0.5 Emmrich (1973) 2437217.562 -964 -0.001 pe 3 Mitchell et al. (1964) 2438698.948 -709 -0.017 pe 1 Haug (1970) 2439076.702 -644 +0.168 vis 0.5 Emmrich (1973) 2440151.420 -459 +0.168 vis 0.5 Emmrich (1973) 2442068.60 -129 +0.29 vis 0.5 Small (1974) 2442817.752 0 +0.039 pe 3 present paper Remark: 1 Observer: Solov'yov MW Cygni The light and colour curves of MW Cyg are plotted in Fig. 20. Its period (somewhat less than six days) is the shortest value when the hump appears on the descending branch of the light curve.
Figure 20 B and B-V curves of MW Cyg When determining the correct value of the period all normal maxima listed in Table 16 were considered except the visual ones. Finally the O-C residuals have been calculated with the formula: C = 2442923.839 + 5.954586d*E There is no sign of period change in the O-C diagram (see Fig. 21), although Tsarevsky (1967) included this Cepheid among the Cepheids with changing period.
Figure 21 O-C diagram of MW Cyg Table 16 O-C residuals for MW Cyg Obs.Max.J.D. E O-C Type w Reference 2416729.471 -4399 -0.144d pg 0.5 Parenago (1940) 2423661.00 -3235 +0.25 pg 0.5 Oosterhoff (1935) 2424678.92 -3064 -0.07 pg 0.5 Oosterhoff (1935) 2425113.90 -2991 +0.23 pg 0.5 Oosterhoff (1935) 2425816.69 -2873 +0.38 pg 0 Oosterhoff (1935) 2426179.71 -2812 +0.17 pg 0.5 Oosterhoff (1935) 2426572.53 -2746 -0.02 pg 0.5 Solov'yov^1 (1946a) 2426644.14 -2734 +0.14 pg 0.5 Oosterhoff (1935) 2427043.52 -2667 +0.56 pg 0 Oosterhoff (1935) 2429001.926 -2338 -0.091 pg 0.5 Parenago (1940) 2429418.75 -2268 -0.09 pg 0.5 Starikova et al. (1946) 2430532.222 -2081 -0.124 pg 1 Solov'yov (1946a) 2431038.435 -1996 -0.050 pg 1 Solov'yov (1946a) 2433884.781 -1518 +0.004 pg 1 Shteiman (1958) 2434539.757 -1408 -0.025 pg 1 Shteiman (1958) 2435677.074 -1217 -0.034 pg 1 Shteiman (1958) 2436802.499 -1028 -0.026 pe 3 Oosterhoff (1960) 2436820.339 -1025 -0.049 pe 3 Weaver et al. (1960) 2436844.37 -1021 +0.16 vis 0.5 Haussler (1964b) 2437249.30 -953 +0.18 vis 0.5 Haussler (1964b) 2437886.46 -846 +0.20 vis 0.5 Haussler (1964b) 2438285.41 -779 +0.19 vis 0.5 Haussler (1964b) 2442923.911 0 +0.072 pe 3 present paper Remark: 1 Observers: Lange and Tsessevich VW Cassiopeiae This Cepheid has a faint companion SW. The present B-V amplitude is less than given in the catalogue compiled by Schaltenbrand and Tammann (1971); this may be an effect caused by this companion. In the course of determining the correct value of the period the normal maxima with a weight of 0.5 were also used. Finally the O-C residuals have been derived using the formula: C = 2442778.693 + 5.993859d*E The O-C diagram in Fig. 23 shows the constancy of the period.
Figure 22 B and B-V curves of VW Cas
Figure 23 O-C diagram of VW Cas Table 17 O-C residuals for VW Cas Obs.Max.J.D. E O-C Type w Reference 2412107.55 -5117 -0.57d pg 0 Oosterhoff (1935) 2413468.57 -4890 -0.15 pg 0.5 Oosterhoff (1935) 2415656.568 -4525 +0.087 p9 0.5 Oosterhoff (1935) 2416124.08 -4447 +0.08 pg 0.5 Tsepova et al. (1948) 2416585.633 -4370 +0.104 pg 0.5 Tsepova et al. (1948) 2418629.84 -4029 +0.41 pg 0 Oosterhoff (1935) 2420751.85 -3675 +0.59 p9 0 Oosterhoff (1935) 2421991.981 -3468 -0.009 pg 0.5 Balanowsky (1924) 2422837.387 -3327 +0.263 pg 0.5 Oosterhoff (1935) 2423472.463 -3221 -0.010 pg 0.5 Balanowsky (1924) 2424065.75 -3122 -0.11 pg 0.5 Oosterhoff (1935) 2425420.21 -2896 -0.27 vis 0.5 Kukarkin (1929) 2426097.911 -2783 +0.128 pg 0.5 Oosterhoff (1935) 2426816.819 -2663 -0.227 pg 0.5 Oosterhoff (1935) Table 17 (cont.) Obs.Max.J.D. E O-C Type w Reference 2428465.07 -2388 -0.29d pg 0.5 Fu De-Lian (1964) 2429142.86 -2275 +0.20 pg 0.5 Tsepova et al. (1948) 2430994.853 -1966 +0.087 pg 0.5 Solov'yov (1954) 2433176.555 -1602 +0.024 pg 0.5 Solov'yov (1954) 2436287.334 -1083 -0.010 pg 0.5 Erleksova (1961) 2436808.793 -996 -0.016 pe 3 Weaver et al. (1960) 2436820.781 -994 -0.016 pe 3 Oosterhoff (1960) 2436880.749 -984 +0.013 pe 3 Bahner et al. (1962) 2437348.429 -906 +0.172 vis 0.5 Berthold (1975) 2439044.497 -623 -0.022 vis 0.5 Berthold (1975) 2442778.699 0 +0.006 pe 3 present paper KL Aquilae According to Madore (1977) this Cepheid is suspected in having a blue photometric companion. The light and colour curves of KL Aql shown in Fig. 24 are normal for a Population I Cepheid but the 2nd Supplement to the G.C.V.S. (Kukarkin et al. 1974) classifies it as a Population II Cepheid.
Figure 24 B and B-V curves of KL Aql The O-C residuals have been computed with the formula: C = 2443338.695 + 6.108015d*E The period of KL Aql has remained constant since the discovery of its light variation (see Fig. 25).
Figure 25 O-C diagram of KL Aql Table 18 O-C residuals for KL Aql Obs.Max.J.D. E O-C Type w Reference 2421484.137 -3578 -0.080d pg 1 Parenago (1940) 2426126.433 -2818 +0.124 vis 1 Parenago^1 (1940) 2426187.441 -2808 +0.052 vis 1 Parenago^2 (1940) 2426981.409 -2678 -0.022 vis 1 Parenago^2 (1940) 2433645.0 -1587 -0.3 vis 0 Solov'yov (1953) 2433700.226 -1578 -0.021 pg 1 Solov'yov (1958a) 2433950.66 -1537 -0.02 pg 0.5 Tsessevich (1953) 2434982.845 -1368 -0.085 pvis 1 Solov'yov (1958a) 2435129.518 -1344 -0.005 pg 1 Solov'yov (1958a) 2435691.73 -1252 +0.27 pg 0 Huth (1966) 2435721.97 -1247 -0.03 pg 0.5 Vasil'yan. et al. (1970) 2436052.17 -1193 +0.34 pg 0 Huth (1966) 2436057.91 -1192 -0.03 pg 0.5 Vasil'yan. et al. (1970) 2436430.50 -1131 -0.03 pg 0.5 Vasil'yan. et al. (1970) 2436436.55 -1130 -0.09 pg 0.5 Huth (1966) 2436754.35 -1078 +0.09 pg 0.5 Huth (1966) 2436790.898 -1072 -0.005 pe 3 Oosterhoff (1960) 2436815.31 -1068 -0.02 pg 0.5 Vasil'yan. et al. (1970) 2436833.661 -1065 +0.002 pe 3 Weaver et al. (1960) 2436864.30 -1060 +0.10 vis 0.5 Voigtlander (1964) 2437188.08 -1007 +0.16 pg 0.5 Huth (1966) 2437273.41 -993 -0.03 pg 0.5 Vasil'yan, et al. (1970) 2437579.15 -943 +0.31 pg 0 Huth (1966) 2437811.35 -905 +0.41 pg 0 Huth (1966) 2437890.33 -892 -0.02 pg 0.5 Vasil'yan. et al. (1970) 2437939.38 -884 +0.17 vis 0.5 Voigtlander (1964) 2438153.50 -849 +0.51 pvis 0 Beyer (1968) 2438232.50 -836 +0.11 vis 0.5 Voigtlander (1964) 2438257.24 -832 +0.41 pg 0 Huth (1966) 2438421.78 -805 +0.04 pvis 0.5 Beyer (1968) 2438446.16 -801 -0.02 pg 0.5 Vasil'yan. et al. (1970) 2438672.27 -764 +0.10 pvis 0.5 Beyer (1968) 2438965.50 -716 +0.14 pvis 0.5 Beyer (1968) 2439295.21 -662 +0.02 pvis 0.5 Beyer (1968) 2441115.392 -364 +0.014 pe 3 Pel (1976) 2443338.696 0 +0.001 pe 3 present paper Remarks: 1 Observer: Blazhko 2 Observer: Nabokov FM Aquilae This Cepheid has a blue photometric companion of spectral type B9 (Madore 1977). As can be seen from Fig. 26, the U-B amplitude is too small.
Figure 26 B, B-V and U-B curves of FM Aql
Figure 27 O-C diagram of FM Aql
The O-C residuals have been calculated with the formulae:
C_{max} = 2442678.222 + 6.114230d*E
C_{med} = 2442677.559 + 6.114230d*E
The period has been constant since the discovery of its light variation (see Fig. 27).
Table 19 O-C residuals for FM Aql
(maximum brightness)
Obs.Max.J.D. E O-C Type W Reference
2421095.021 -3530 +0.031d pg 1 Kukarkin (1940)
2425894.631 -2745 -0.030 vis 1 Ahnert (1938)
2425919.149 -2741 +0.031 vis 1 Lause (1930)
2426157.469 -2702 -0.104 vis 1 Kukarkin (1940)
2426163.675 -2701 -0.012 vis 1 Ahnert (1938)
2426555.059 -2637 +0.062 vis 1 Ahnert (1938)
2427979.805 -2404 +0.192 vis 0.5 Dziewulski et al. (1956)
2428627.686 -2298 -0.035 vis 1 Ahnert (1938)
2432962.724 -1589 +0.013 pe 3 Eggen (1951)
2433757.732 -1459 +0.172 vis 1 Filin (1952)
2435292.245 -1208 +0.013 pe 2 Irwin (1961)
2435500.086 -1174 -0.030 pe 2 Walraven et al. (1958)
2437108.485 -911 +0.327 pg 0 Huth (1964)
2437187.583 -898 -0.060 pe 3 Mitchell et al. (1964)
2440819.509 -304 +0.013 pe 3 Pel (1976)
2442678.229 0 +0.007 pe 3 present paper
Table 20 O-C residuals for FM Aql
(median brightness)
Obs.Med.J.D. E O-C Type W Reference
2432962.063 -1589 +0.015d pe 3 Eggen (1951)
2437186.959 -898 -0.021 pe 3 Mitchell et al. (1964)
2440818.818 -304 -0.015 pe 3 Pel (1976)
2442677.581 0 +0.022 pe 3 present paper
V 538 Cygni
Figure 28 B and B-V curves of V 538 Cyg The light and colour curves of this variable are shown in Fig. 28. When the correct value of the period was being determined all the normal maxima were considered, i.e. those with low weight too. The O-C residuals have been derived using the formula: C = 2442772.924 + 6.118961d*E The O-C diagram is based on only four points so it is premature to declare the constancy of the period.
Figure 29 O-C diagram of V 538 Cyg Table 21 O-C residuals for V 538 Cyg Obs.Max.J.D. E O-C Type w Reference 2432799.13 -1630 +0.11d pg 0.5 Manova (1950) 2435160.979 -1244 +0.042 pg 0.5 Nikulina (1970) 2436806.898 -975 -0.039 pe 3 Oosterhoff (1960) 2442772.938 0 +0.014 pe 3 present paper TX Delphini This Cepheid belongs to Population II (Kukarkin et al. 1969-1970), although the light and colour curves in Fig. 30 do not differ from those of Population I Cepheids with the same period. Table 22 O-C residuals for TX Del Obs.Max.J.D. E O-C Type w Reference 2428067.22 -2413 -1.45d vis 0 Gur'yev (1935) 2428801.658 -2294 -0.760 pg 0.5 Leibovich (1952) 2429140.805 -2239 -0.738 pg 0.5 Leibovich (1952) 2429461.395 -2187 -0.775 pg 0.5 Leibovich (1952) 2429868.309 -2121 -0.811 pg 0.5 Leibovich (1952) 2429893.07 -2117 -0.71 pg 0.5 Vasil'yan. et al. (1970) 2430195.118 -2068 -0.795 pg 0.5 Leibovich (1952) 2430386.52 -2037 -0.54 pg 0.5 Vasil'yan. et al. (1970) 2430651.865 -1994 -0.325 vis 0 Model, Lochel (1964) 2430978.550 -1941 -0.434 vis 0.5 Model, Lechet (1964) 2431324.166 -1885 -0.108 vis 0 Model, Lochel (1964) 2431373.06 -1877 -0.54 pg 0.5 Vasil'yan. et al. (1970) 2433155.08 -1588 -0.47 pg 0.5 Vasil'yan. et al. (1970) 2433870.53 -1472 -0.26 pg 0.5 Vasil'yan. et al. (1970) 2434234.30 -1413 -0.28 pg 0.5 Vasil'yan. et al. (1970) 2434604.35 -1353 -0.19 pg 0.5 Vasil'yan. et al. (1970) 2434992.85 -1290 -0.14 pg 0.5 Vasil'yan. et al. (1970) Table 22 (cont.) Obs.Max.J.D. E O-C Type w Reference 2435363.03 -1230 +0.09d pg 0.5 Vasil'yan. et al. (1970) 2435664.972 -1181 -0.101 pe 3 Walraven et al. (1958) 2435720.51 -1172 -0.06 pg 0.5 Vasil'yan. et al. (1970) 2435936.746 -1137 +0.373 pg 0 Nikulina et al. (1959) 2436065.84 -1116 -0.02 pg 0.5 Vasil'yan. et al. (1970) 2436460.50 -1052 +0.03 pg 0.5 Vasil'yan. et al. (1970) 2436818.04 -994 -0.06 pg 0.5 Vasil'yan. et al. (1970) 2437182.12 -935 +0.23 pg 0.5 Vasil'yan. et al. (1970) 2437292.994 -917 +0.122 pe 3 Mitchell et al. (1964) 2437576.53 -871 +0.03 pg 0.5 Vasil'yan. et al. (1970) 2437897.32 -819 +0.19 pg 0.5 Vasil'yan. et al. (1970) 2438273.17 -758 -0.08 pg 0.5 Vasil'yan. et al. (1970) 2438612.34 -703 -0.04 pg 0.5 Vasil'yan. et al. (1970) 2438994.48 -641 -0.18 pg 0.5 Vasil'yan. et al. (1970) 2439099.438 -624 -0.045 pe 3 Takase (1969) 2440819.842 -345 +0.071 pe 3 Pel (1976) 2442947.033 0 +0.024 pe 3 present paper
Figure 30 B, B-V and U-B curves of TX Del When determining the correct value of the period the normal maxima with low weight were also taken into account before the change in the period. The O-C residuals have been computed with the formula: C = 2442947.009 + 6.165907d*E The O-C diagram in Fig. 31 shows one period change: before J.D, 2436600 P = 6.166585d , after J.D. 2436600 P = 6.165907d .
Figure 31 O-C diagram of TX Del V 733 Aquilae This Cepheid has not previously been observed photoelectrically. Its light and colour curves are plotted in Fig. 32. The amplitude of the light variation is small but the light curve is not symmetrical.
Figure 32 B and B-V curves of V 733 Aql The O-C residuals have been calculated with the ephemeris: C = 2442597.207 + 6.178748d*E There is no sign of a change in the period (see Fig. 33), although Satyvaldiev (1962) reported on a period change at about J.D. 2436000.
Figure 33 O-C diagram of V 733 Aql Table 23 O-C residuals for V 733 Aql Obs.Max.J.D. E O-C Type w Reference 2417097.088 -4127 -0.426d pg 0 Satyvaldiev^1 (1962) 2429949.447 -2047 +0.137 pg 0.5 Satyvaldiev^1 (1962) 2433187.112 -1523 +0.138 pg 1 Filatov (1962) 2433872.813 -1412 -0.002 pg 1 Filatov (1962) 2434076.750 -1379 +0.036 pg 1 Satyvaldiev (1962) 2434324.236 -1339 +0.373 pvis 0 Satyvaldiev (1962) 2434521.569 -1307 -0.014 pg 1 Filatov (1962) 2434688.267 -1280 -0.143 pg 1 Satyvaldiev (1962) 2435281.723 -1184 +0.154 pg 1 Filatov (1962) 2435694.50 -1117 -1.05 pg 0 Busch, Wenzel (1960) 2435997.76 -1068 -0.54 pg 0 Busch, Wenzel (1960) 2436374.87 -1007 -0.34 pg 0 Busch, Wenzel (1960) 2436381.259 -1006 -0.128 pg 1 Satyvaldiev^1 (1962) 2436424.598 -999 -0.040 pg 1 Filatov (1962) 2436467.81 -992 -0.08 pg 0.5 Busch, Wenzel (1960) 2436716.043 -952 +1.004 pg 0 Busch, Wenzel (1960) 2436758.612 -945 +0.322 pvis 0 Satyvaldiev (1962) 2436851.221 -930 +0.250 pg 0.5 Busch (1961) 2436875.736 -926 +0.050 pg 1 Dultsev (1963) 2436949.707 -914 -0.124 pg 1 Satyvaldiev^1 (1962) 2437253.276 -865 +0.686 pg 0 Busch (1961) 2442597.232 0 +0.025 pe 3 present paper Remark: 1 Observer: Tsessevich VV Cassiopeiae This variable has a B7 photometric companion (Madore 1977). The light and colour curves of VV Cas are plotted in Fig. 34. The normal maxima with weight of 0.5 listed in Table 24 were also taken into account when determining the correct value of the period. The O-C residuals have been derived using the formula: C = 2442836.853 + 6.207059d*E As shown by the O-C diagram (Fig. 35), the period has changed on one occasion: before J.D. 2432500 P = 6.207510d after J.D. 2432500 P = 6.207059d
Figure 34 B and B-V curves of VV Cas
Figure 35 O-C diagram of VV Cas Table 24 O-C residuals for VV Cas Obs.Max.J.D. E O-C Type w Reference 2417262.646 -4120 -1.124d pg 0.5 Merzlyakov (1957) 2421117.51 -3499 -0.84 vis 0.5 Hoffmeister (1923) 2421576.89 -3425 -0.79 vis 0.5 Hoffmeister (1923) 2422514.159 -3274 -0.783 pg 0.5 Robinson (1933) 2422806.1 -3227 -0.6 vis 0.5 Hoffmeister (1923) 2426319.389 -2661 -0.480 vis 1 Kukarkin (1940) 2428440.00 -2319 -2.68 pg 0 Fu De-Lian (1964) 2429156.266 -2204 -0.229 pg 0.5 Merzlyakov (1957) 2434655.901 -1318 -0.048 pg 1 Merzlyakov (1957) Table 24 (cont.) Obs.Max.J.D. E O-C Type w Reference 2436816.001 -970 -0.005d pe 3 Oosterhoff (1960) 2436822.233 -969 +0.020 pe 3 Weaver et al. (1960) 2436853.252 -964 +0.004 pe 3 Bahner et al. (1962) 2437213.268 -906 +0.010 pe 2 Mitchell et al. (1964) 2442836.847 0 -0.006 pe 3 present paper CR Cephei The variable star CR Cep is a small amplitude Cepheid with a non-symmetrical light curve (see Fig. 36). The O-C residuals
Figure 36 B and B-V curves of CR Cep
Figure 37 O-C diagram of CR Cep have been computed with the formula: C = 2442774.236 + 6.232964d*E The O-C diagram in Fig. 37 shows one period change. Neither the time of the change in the period nor the value of the former period can be determined for lack of sufficient number of points in the O-C diagram. The only certain fact is that the period change occurred before J.D. 2428000. Table 25 O-C residuals for CR Cep Obs.Max.J.D. E O-C Type w Reference 2415005.7 -4455 -0.7d pg 0.5 Oosterhoff (1960) 2417200.2 -4103 -0.2 pg 0.5 Oosterhoff (1960) 2428045.680 -2363 -0.062 pg 1 Parenago (1938b) 2428750.076 -2250 +0.009 vis 1 Florya (1949) 2429142.758 -2187 +0.014 vis 1 Florya (1949) 2429479.460 -2133 +0.136 vis 0.5 Florya (1949) 2433362.470 -1510 +0.010 pg 0.5 Timofeyeva (1967) 2434366.226 -1349 +0.258 pg 0.5 Romano (1956) 2436123.644 -1067 -0.019 pg 1 Makarenko (1969) 2436479.027 -1010 +0.085 pg 1 Makarenko (1969) 2436809.309 -957 +0.020 pe 3 Oosterhoff (1960) 2436865.432 -948 +0.046 pe 3 Bahner et al. (1962) 2437021.276 -923 +0.066 pg 1 Makarenko (1969) 2437214.339 -892 -0.093 pe 3 Mitchell et al. (1964) 2437544.783 -839 +0.004 pg 1 Girnyak (1969) 2437569.684 -835 -0.027 pg 1 Makarenko (1969) 2437937.440 -776 -0.016 pg 1 Makarenko (1969) 2438267.747 -723 -0.056 pg 1 Girnyak (1969) 2438299.037 -718 +0.069 pg 1 Makarenko (1969) 2438847.501 -630 +0.032 pg 1 Girnyak (1969) 2438859.948 -628 +0.013 pg 1 Makarenko (1969) 2439047.078 -598 +0.154 vis 0.5 Berthold (1975) 2441602.436 -188 -0.003 vis 0.5 Berthold (1975) 2442774.223 0 -0.013 pe 3 present paper RS Cassiopeiae The light and colour curves of this variable are shown in
Figure 38 B and B-V curves of RS Cas
Fig. 38. The O-C residuals in Table 26 have been computed with the formula:
C = 2442773.487 + 6.295983d*E
As is shown by the O-C diagram in Fig. 39, the period has changed on one occasion:
before J.D. 2434900 P = 6.295623d
after J.D. 2434900 P = 6.295983d
If the O-C diagram is approximated by a parabolic line (continuous period change), the
equation of the best fitting parabola is:
C_{par} = 2442773.461 + 6.295993*E + 6.74*10^{-8}*E^2
Figure 39 O-C diagram of RS Cas Table 26 O-C residuals for RS Cas Obs.Max.J.D. E O-C Type w Reference 2416740.786 -4135 +1.189d vis 0.5 Kandiba et al.^1 (1935) 2417187.679 -4064 +1.067 pg 1 Kandiba et al. (1935) 2417357.706 -4037 +1.102 vis 1 Kandiba et al.^1 (1935) 2417515.036 -4012 +1.033 vis 1 Haynes (1907) 2417521.205 -4011 +0.906 vis 1 Whitney (1907) Furness^2 (1913) 2417792.103 -3968 +1.077 vis 0.5 Zeipel (1908) 2419617.580 -3678 +0.718 pg 0.5 Robinson (1933) 2421367.807 -3400 +0.662 pg 1 Jordan (1929) 2424043.512 -2975 +0.574 vis 0.5 Kandiba et al.^1 (1935) 2425126.358 -2803 +0.511 pg 1 Schneller (1931) 2427751.571 -2386 +0.299 pg 0.5 Tolmar (1940a) 2429098.898 -2172 +0.286 pg 1 Tolmar (1940a) 2429470.457 -2113 +0.382 pg 0.5 Tolmar (1940a) 2430698.041 -1918 +0.249 pg 1 Solov'yov (1954) 2431012.634 -1868 +0.043 pg 0.5 Vasil'yanovskaya (1948) 2431359.126 -1813 +0.256 pg 1 Solov'yov (1954) 2433184.831 -1523 +0.126 pg 1 Solov'yov (1954) 2435873.005 -1096 -0.085 pg 0.5 Zonn, Semeniuk (1959) 2436401.84 -1012 -0.11 pg 0.5 Rubashevsky (1962) 2436767.158 -954 +0.039 pe 3 Weaver et al. (1960) 2436792.303 -950 0.000 pe 3 Oosterhoff (1960) Table 26 (cont.) Obs.Max.J.D. E O-C Type w Reference 2436880.430 -936 -0.17d pe 3 Bahner et al. (1962) 2437025.500 -913 +0.245 vis 0.5 Haussler (1973) 2437220.404 -882 -0.026 pe 3 Mitchell et al. (1964) 2437365.373 -859 +0.135 vis 0.5 Haussler (1973) 2438542.68 -672 +0.09 pg 0.5 Ahnert (1966) 2439046.153 -592 -0.112 vis 0.5 Haussler (1973) 2439436.312 -530 -0.304 vis 0 Haussler (1973) 2440097.502 -425 -0.192 vis 0.5 Haussler (1973) 2440865.701 -303 -0.103 pg 0.5 Rummler (1977) 2441300.450 -234 +0.223 pg 0.5 Rummler (1977) 2441615.398 -184 +0.372 p9 0 Rummler (1977) 2441967.408 -128 -0.193 pg 0.5 Rummler (1977) 2442314.250 -73 +0.370 pg 0 Rummler (1977) 2442678.758 -15 -0.289 pg 0 Rummler (1977) 2442773.489 0 +0.002 pe 3 present paper Remarks: 1 Observer: Blazhko; 2 Observer: Whitney X Vulpeculae The light and colour curves of this variable are shown in
Figure 40 B, B-V and U-B curves of X Vul Fig. 40. The present U-B amplitude is smaller than expected (Schaltenbrand and Tammann 1971). The O-C residuals have been calculated using the formula: C = 2442665.932 + 6.319543d*E The O-C diagram in Fig. 41 shows one period change. Neither the time of the change in the period nor the value of the former period can be determined since the period change occurred before J.D. 2427000 when the reliability of the O-C diagram is not good.
Figure 41 O-C diagram of X Vul Table 27 O-C residuals for X Vul Obs.Max.J.D. E O-C Type w Reference 2416756.3 -4100 +0.5d vis 0.5 Duner et al.^1 (1904) 2417066.09 -4051 +0.63 vis 0.5 Seares (1907a) 2417432.55 -3993 +0.55 vis 0.5 Seares (1907a) 2417470.166 -3987 +0.252 vis 1 Luizet (1907b) 2417893.435 -3920 +0.112 vis 0.5 Zeipel (1908) 2419701.18 -3634 +0.47 vis 0.5 Luizet (1914) 2419972.80 -3591 +0.35 vis 0.5 Luizet (1914) 2420636.248 -3486 +0.243 pg 0.5 Robinson (1933) 2425843.478 -2662 +0.169 pg 0.5 Nassau, Townson (1932) 2426481.643 -2561 +0.061 vis 1 Kukarkin (1940) 2427499.037 -2400 +0.008 vis 0.5 Nassau, Ashbrook (1943) 2428004.616 -2320 +0.024 pg 0.5 Nassau, Ashbrook (1943) 2428314.212 -2271 -0.038 pg 1 Azhusenis (1956) 2428453.05 -2249 -0.23 pg 0.5 Fu De-Lian (1964) 2428857.785 -2185 +0.054 pg 0.5 Nassau, Ashbrook (1943) 2428984.128 -2165 +0.007 pg 1 Azhusenis (1956) 2430128.29 -1984 +0.33 vis 0.5 Ashbrook (1943) 2432421.920 -1621 -0.033 pg 0.5 Davis (1949) 2432794.98 -1562 +0.17 pg 0.5 Wachmann (1964a) 2433117.093 -1511 -0.010 pe 3 Eggen (1951) 2433692.141 -1420 -0.040 pg 1 Chuprina (1954) 2433868.946 -1392 -0.182 pg 1 Chuprina^2 (1954) 2434122.06 -1352 +0.15 pg 0.5 Wachmann (1964a) 2434627.63 -1272 +0.16 pg 0.5 Wachmann (1964a) 2435006.72 -1212 +0.07 pg 0.5 Wachmann (1964a) 2435303.701 -1165 +0.037 pg 0.5 Chuprina (1957) 2435354.434 -1157 +0.213 pe 1 Walraven et al. (1958) 2435360.66 -1156 +0.12 pg 0.5 Wachmann (1964a) Table 27 (cont.) Obs.Max.J.D. E O-C Type w Reference 2435695.36 -1103 -0.12d pg 0.5 Huth (1966) 2436023.83 -1051 -0.26 pg 0.5 Huth (1966) 2436485.46 -978 +0.04 pg 0.5 Huth (1966) 2436839.40 -922 +0.09 pg 0.5 Huth (1966) 2436858.191 -919 -0.081 vis 0.5 Busch (1963) 2437174.33 -869 +0.08 pg 0.5 Huth (1966) 2437205.847 -864 0.000 pe 3 Mitchell et al. (1964) 2437357.564 -840 +0.048 pg 1 Boyko (1970) 2437641.90 -795 +0.01 pg 0.5 Huth (1966) 2437919.746 -751 -0.209 vis 0.5 Busch (1963) 2437932.77 -749 +0.18 pg 0.5 Huth (1966) 2438172.84 -711 +0.10 pg 0.5 Huth (1966) 2438640.53 -637 +0.15 pg 0.5 Huth (1966) 2439291.295 -534 -0.001 p9 1 Boyko (1970) 2442665.923 0 -0.009 pe 3 present paper Remarks: 1 Observer: Blazhko; 2 Observer: Tsessevich RR Lacertae The light and colour curves of RR Lac are plotted in Fig. 42.
Figure 42 B, B-V and U-B curves of RR Lac
The O-C residuals have been computed with the formulae:
C_{max} = 2442776.686 + 6.416243d*E ,
C_{med} = 2442775.898 + 6.416243d*E .
One change in the period can be suspected (see Fig. 43):
before J.D. 2431600 P = 6.416146 ,
after J.D. 2431600 P = 6.416243 .
Figure 43 O-C diagram of RR Lac Table 28 O-C residuals for RR Lac (maximum brightness) Obs.Max.J.D. E O-C Type w Reference 2417914.015 -3875 +0.271d vis 1 Enebo (1908) 2418330.952 -3810 +0.152 vis 1 Enebo (1909) 2418555.557 -3775 +0.188 vis 1 Bilt (1926b) 2419011.107 -3704 +0.185 vis 1 Enebo (1912) 2419376.875 -3647 +0.227 vis 1 Bilt (1926b) 2419434.331 -3638 -0.063 pg 0 Robinson (1933) 2420005.552 -3549 +0.112 pg 2 Hertzsprung (1922) 2420217.338 -3516 +0.162 vis 1 Bilt (1926b) 2421429.921 -3327 +0.075 pg 2 Hertzsprung (1922) 2421667.365 -3290 +0.118 pg 1 Jordan (1929) 2424856.5 -2793 +0.4 vis 0 Selivanov (1929) 2425747.99 -2654 +0.01 pg 0.5 Kiehl, Hopp (1977) 2425838.081 -2640 +0.277 vis 0.5 Parenago (1938a) 2425850.797 -2638 +0.160 vis 1 Beyer (1934b) 2426312.834 -2566 +0.228 vis 0.5 Terkán (1935) 2426530.843 -2532 +0.084 vis 1 Kukarkin (1940) 2426537.221 -2531 +0.046 pg 1 Zonn (1933) 2426607.914 -2520 +0.160 vis 1 Beyer (1934b) 2426633.496 -2516 +0.077 vis 1 Lassovszky (1934) 2426762.084 -2496 +0.341 vis 0.5 Dziewulski et al. (1946) 2426806.984 -2489 +0.327 vis 0.5 Dziewulski et al. (1946) 2426870.80 -2479 -0.02 pg 0.5 Kiehl, Hopp (1977) 2427095.468 -2444 +0.080 pg 1 Zonn (1933) 2427294.338 -2413 +0.046 vis 1 Florya et al. (1953) 2427403.406 -2396 +0.038 vis 1 Lassovszky (1934) 2428269.609 -2261 +0.048 vis 0.5 Dziewulski et al. (1946) 2428346.526 -2249 -0.029 pg 0.5 Dziewulski et al. (1946) 2428461.98 -2231 -0.07 pg 0.5 Fu De-Lian (1964) Table 28 (cont.) Obs.Max.J.D. E O-C Type w Reference 2428558.287 -2216 -0.05d pg 0.5 Dziewulski et al. (1946) 2428751.422 -2186 +0.643 pg 0 Gur'yev (1938) 2429045.94 -2140 +0.01 pg 0.5 Katz (1946) 2432998.350 -1524 +0.018 pe 3 Eggen (1951) 2433537.316 -1440 +0.020 pg 1 Solov'yov (1952) 2434968.133 -1217 +0.015 pg 1 Azarnova (1957) 2436033.214 -1051 -0.001 pe 3 Bahner et al. (1971) 2436835.238 -926 -0.007 pe 3 Bahner et al. (1962) 2437213.761 -867 -0.042 pe 3 Mitchell et al. (1964) 2437579.580 -810 +0.051 pg 1 Girnyak (1964) 2438240.338 -707 -0.064 pg 1 Girnyak (1964) 2440582.350 -342 +0.019 pe 3 Asteriadis et al. (1977) 2442776.720 0 +0.034 pe 3 present paper Table 29 O-C residuals for RR Lac (median brightness) Obs.Med.J.D. E O-C Type w Reference 2420004.737 -3549 +0.85d pg 2 Hertzsprung (1922) 2421429.144 -3327 +0.086 pg 2 Hertzsprung (1922) 2436032.418 -1051 -0.009 pe 3 Bahner et al. (1971) 2440581.548 -342 +0.005 pe 3 Asteriadis et al. (1977) 2442775.905 0 +0.007 pe 3 present paper AW Persei The light and colour curves of this Cepheid are shown in Fig. 44. AW Per was reported to be a component of a spectroscopic binary system (Miller and Preston 1964). On the basis of the available radial velocity measurements Lloyd Evans (1968) determined the lowest value of the orbital period to be 1200 days. Using more recent radial velocity measurements McNamara and Chapman (1977) concluded that the orbital period was longer than 20 years. The presence of the B7 companion can also be pointed out using only photometric data (Madore 1977). The O-C residuals have been calculated with the formula: C = 2442709.059 + 6.463589d*E If the first point in the O-C diagram in Fig. 45 is real, a period change took place before J.D. 2426000. It is even more interesting that a simple eye inspection can reveal a sinusoidal wave in the O-C diagram which is a direct result of the orbital motion of AW Per around the centre of mass of the binary system. The phenomenon is similar to the case of FF Aql (Paper I, p. 94). A search for the period of this long term modulation gave
Figure 44 B, B-V and U-B curves of AW Per
Figure 45 O-C diagram of AW Per
P_{orb} = 10300 ą 800 days, as the best result. The resulting light-time diagram versus the
orbital phase is plotted in Fig. 46. In constructing this diagram the O-C values based on
visual observations were averaged into one point. The orbital phases have been computed with
the formula:
Epoch + phase = (J.D. - 2400000)*10300^{-1}
The observed maxima, the corresponding O-C residuals and the orbital phases are listed in
Table 31. The value of a* sin i can be
determined from the amplitude of the O-C variation curve. The result is: a* sin i = 1.6x10^9 km.
Figure 46 O-C variations due to the orbital motion Table 30 O-C residuals for AW Per Obs.Max.J.D. E O-C Type w Reference 2416512.64 -4053 +0.50d pg 0.5 Kukarkin (1930) 2425832.8 -2611 +0.2 vis 0.5 Guthnick et al.^1 (1930) 2425845.669 -2609 +0.114 vis 1 Kukarkin (1940) 2426007.145 -2584 0.000 vis 0.5 Jacchia^2 (1930) 2426019.929 -2582 -0.143 vis 1 Jacchia (1930) 2426634.109 -2487 -0.004 vis 1 Kukarkin (1940) 2429070.812 -2110 -0.074 pg 1 Opolski (1948) 2432865.073 -1523 +0.060 pg 1 Erleksova (1961) 2434765.577 -1229 +0.269 pg 0.5 Erleksova (1961) 2435463.438 -1121 +0.062 pg 1 Erleksova (1961) 2436109.735 -1021 0.000 pe 3 Bahner et al. (1977) 2436426.431 -972 -0.019 pg 1 Erleksova (1961) 2436820.711 -911 -0.018 pe 3 Oosterhoff (1960) 2436827.181 -910 -0.012 pe 3 Weaver et al. (1960) 2439503.063 -496 -0.056 pe 3 Wamsteker (1972) 2440996.204 -265 -0.004 pe 2 Evans (1976) 2442709.062 0 +0.003 pe 3 present paper Remarks: 1 Observer: Kanda; 2 Observer: Dallaporta Table 31 Obs.Max.J.D. O-C phase Obs.Max.J.D. O-C phase 2426168.714 -0.011d .541 2436820.711 -0.018d .575 2429070.812 -0.074 .822 2436827.181 -0.012 .575 2432865.073 +0.060 .191 2439503.063 -0.056 .835 2435463.438 +0.062 .443 2440996.204 -0.004 .980 2436109.735 0.000 .506 2442709.062 +0.003 .147 2436426.431 -0.019 .537 CS Monocerotis There is a faint companion NE of the variable. This may be the reason that the B and the B-V amplitudes of the variable (see Fig. 47) are smaller than given in the catalogue compiled by Schaltenbrand and Tammann (1971).
Figure 47 B and B-V curves of CS Mon
Figure 48 O-C diagram of CS Mon Table 32 O-C residuals for CS Mon Obs.Max.J.D. E O-C Type w Reference 2430758.58 -1770 +0.54d pg 0.5 Ahnert (1947) 2434406.665 -1228 -0.072 pg 1 Bogdanov (1974) 2435544.469 -1059 +0.037 pe 1 Walraven et al. (1958) 2436964.811 -848 -0.056 pg 1 Bogdanov (1974) 2437914.158 -707 +0.090 pe 1 Eggen (1969) 2440855.969 -270 +0.052 pe 3 Pel (1976) 2442673.488 0 -0.047 pe 3 present paper The O-C residuals have been derived using the formula: C = 2442673.535 + 6.731920d*E The period has been constant since the discovery of the light variation of CS Mon. AO Aurigae The light curve plotted in Fig. 49 is the first reliable photoelectric light curve of this faint Cepheid. When determining the correct value of the period the normal maxima with a weight of 0.5 were also used. The O-C residuals have been computed with the formula: C = 2442815.860 + 6.763006d*E The O-C diagram in Fig. 50 can be approximated by a straight line, i.e. the period is constant.
Figure 49 B and B-V curves of AO Aur
Figure 50 O-C diagram of AO Aur Table 33 O-C residuals for AO Aur Obs.Max.J.D. E O-C Type w Reference 2418651.555 -3573 -0.085d pg 0.5 Reinmuth (1930) 2418739.308 -3560 -0.251 pg 0.5 Parenago (1934b) 2426523.68 -2409 -0.10 pg 0.5 Rugemer (1935) 2426942.9 -2347 -0.2 vis 0.5 Pedersen (1936) 2427132.476 -2319 +0.027 vis 1 Beyer (1934a) 2427335.463 -2289 +0.124 vis 1 Beyer (1934a) 2432867.714 -1471 +0.236 pg 1 Shakhovskaya (1964) 2435498.721 -1082 +0.433 pg 0.5 Shakhovskaya (1964) 2436850.986 -882 +0.097 pe 1 Weaver et al. (1960) 2436979.279 -863 -0.107 pg 1 Shakhovskaya (1964) 2442815.764 0 -0.096 pe 3 present paper eta Aquilae The light and colour curves of this very bright Cepheid variable are shown in Fig. 51. The V amplitude derived from the
Figure 51 B, B-V and U-B curves of eta Aql
present photometry is less whereas the U-B amplitude is greater than the corresponding
values taken from the catalogue (Schaltenbrand and Tammann 1971).
The large number of photoelectric observational series has made it possible to
construct the O-C diagram not only for the maximum brightness but also for the median
brightness. The O-C residuals have been calculated with the formulae:
C_{max} = 2442794.773 + 7.176735d*E ,
C_{med} - 2442793.855 + 7.176735d*E .
The O-C diagram in Fig. 52 can well be approximated by a parabolic curve, i.e. the period
has been changing continuously since the discovery of the light variation of eta Aql. The
equation of the parabolic curve for the maximum brightness is:
C_{par} = 2442794.773 + 7.176735*E + 2.18*10^{-8}*E^2 .
Figure 52 O-C diagram of eta Aql Table 34 O-C residuals for n Aql (maximum brightness) Obs.Max.J.D. E O-C Type w Reference 2372974.375 -9729 +2.057d vis 1 Pigott (1785, 1786) 2373242.4 -9692 +4.5 vis 0 Dreyer^1 (1918) 2373627.64 -9638 +2.24 vis 0.5 Wurm (1811, 1813) 2374732.96 -9484 +2.34 vis 0.5 Wurm (1811, 1813) 2376161.03 -9285 +2.24 vis 0.5 Wurm (1811, 1813) 2377337.67 -9121 +1.90 vis 0.5 Wurm (1811, 1813) 2379490.69 -8821 +1.90 vis 0.5 Wurm (1811, 1813) 2380559.76 -8672 +1.63 vis 0.5 Wurm (1811, 1813) 2382741.50 -8368 +1.65 vis 0.5 Wurm (1811, 1813) 2385109.938 -8038 +1.761 vis 0.5 Westphal (1818) 2387463.409 -7710 +1.263 vis 1 Muller^2 (1925) 2388805.484 -7523 +1.288 vis 1 Muller^2 (1925) Table 34 .(cont.) Obs.Max.J.D. E O-C Type w Reference 2393376.905 -6886 +1.129d vis 1 Argelander (1869) 2393707.131 -6840 +1.225 vis 1 Argelander (1869) 2393821.756 -6824 +1.023 vis 1 Hagen^3 (1903) 2394051.380 -6792 +0.991 vis 1 Argelander (1869) 2394453.322 -6736 +1.036 vis 1 Argelander (1869) 2394611.136 -6714 +0.962 vis 1 Hagen^3 (1903) 2394769.094 -6692 +1.032 vis 1 Argelander (1869) 2395185.296 -6634 +0.983 vis 1 Argelander (1869) 2395200.224 -6632 +1.558 vis 0 Schmidt (1857a) 2395522.878 -6587 +1.258 vis 0.5 Schmidt (1857a) 2395551.255 -6583 +0.929 vis 1 Hagen^3 (1903) 2395551.391 -6583 +1.065 vis 1 Argelander (1869) 2395874.175 -6538 +0.895 vis 1 Argelander (1869) 2396261.541 -6484 +0.718 vis 1 Argelander (1869) 2396283.351 -6481 +0.998 vis 0.5 Schmidt (1857a) 2396396.19 -6465 -0.99 vis 0 Johnson (1856) 2396426.683 -6461 +0.795 vis 1 Hagen^3 (1903) 2396613.685 -6435 +1.202 vis 0.5 Schmidt (1857a) 2396993.874 -6382 +1.024 vis 0.5 Schmidt (1857a) 2397352.656 -6332 +0.969 vis 1 Argelander (1869) 2397395.573 -6326 +0.826 vis 1 Hagen^3 (1903) 2397711.653 -6282 +1.129 vis 0.5 Schmidt (1857a) 2397718.608 -6281 +0.908 vis 1 Argelander (1869) 2398084.609 -6230 +0.895 vis 1 Argelander (1869) 2398106.369 -6227 +1.125 vis 0.5 Schmidt (1857a) 2398414.885 -6184 +1.041 vis 0.5 Schmidt (1857a) 2398421.883 -6183 +0.863 vis 1 Hagen^3 (1903) 2398429.109 -6182 +0.912 vis 1 Argelander (1869) 2398680.075 -6147 +0.692 vis 0.5 Nielsen^4 (1931) 2398780.686 -6133 +0.829 vis 1 Argelander (1869) 2398802.079 -6130 +0.692 vis 0.5 Schmidt (1857a) 2398816.210 -6128 +0.469 vis 0.5 Schonfeld (1861) 2399175.853 -6078 +1.275 vis 0 Schmidt (1858b) 2399196.587 -6075 +0.479 vis 0.5 Schonfeld (1861) 2399196.852 -6075 +0.744 vis 1 Argelander (1869) 2399455.111 -6039 +0.641 vis 1 Hagen^3 (1903) 2399519.614 -6030 +0.553 vis 0.5 Schon (1861) 2399541.797 -6027 +1.206 vis 0 Schmidt (1858b) 2399548.651 -6026 +0.883 vis 1 Argelander (1869) 2399570.167 -6023 +0.869 vis 1 Zinner, Wachmann^5 (1931) 2399900.206 -5977 +0.778 vis 1 Argelander (1869) 2399907.526 -5976 +0.921 vis 0.5 Schmidt (1859) 2399943.175 -5971 +0.687 vis 0.5 Auwers (1859) 2400237.465 -5930 +0.731 vis 1 Argelander (1869) 2400265.899 -5926 +0.458 vis 0.5 Schmidt (1660a) 2400345.043 -5915 +0.658 vis 0.5 Hagen^3 (1903) 2400352.169 -5914 +0.607 vis 1 Zinner, Wachmann^5 (1931) 2400646.369 -5873 +0.561 vis 0.5 Schmidt (1861) 2401026.824 -5820 +0.649 vis 0.5 Schmidt (1862) 2401385.376 -5770 +0.364 vis 0.5 Schmidt (1863) 2401407.30 -5767 +0.76 vis 0.5 Argelander (1869) 2401758.446 -5718 +0.244 vis 0.5 Schmidt (1864) 2402103.076 -5670 +0.390 vis 0.5 Schmidt (1865) 2402447.778 -5622 +0.609 vis 1 Valentiner^6 (1900) 2402476.448 -5618 +0.572 vis 0.5 Schmidt (1866) Table 34 (cont.) Obs.Max.J.D. E O-C Type w Reference 2402828.175 -5569 +0.639d vis 1 Valentiner^6 (1900) 2402842.370 -5567 +0.481 vis 0.5 Schmidt (1867) 2403151.203 -5524 +0.714 vis 1 Valentiner^6 (1900) 2403201.246 -5517 +0.520 vis 0.5 Schmidt (1868) 2403495.761 -5476 +0.789 vis 1 Valentiner^6 (1900) 2403574.122 -5465 +0.206 vis 0.5 Schmidt (1869) 2403581.672 -5464 +0.579 vis 1 Zinner, Wachmann^5 (1931) 2403911.589 -5418 +0.366 vis 0.5 Schmidt 0 870) 2403947.745 -5413 +0.639 vis 1 Valentiner^6 (1900) 2404284.954 -5366 +0.541 vis 1 Valentiner^6 (1900) 2404306.298 -5363 +0.355 vis 0.5 Schmidt (1871) 2404320.694 -5361 +0.397 vis 0.5 Hagen^3 (1903) 2404428.631 -5346 +0.683 vis 1 Zinner, Wachmann^5 (1931) 2404664.986 -5313 +0.206 vis 0.5 Schmidt (1872) 2404672.514 -5312 +0.557 vis 1 Valentiner^6 (1900) 2405031.145 -5262 +0.352 vis 0.5 Schmidt (1873) 2405031.354 -5262 +0.561 vis 1 Valentiner^6 (1900) 2405404.072 -5210 +0.088 vis 0 Schmidt (1874) 2405440.472 -5205 +0.605 vis 1 Valentiner^6 (1900) 2405741.913 -5163 +0.623 vis 1 Valentiner^6 (1900) 2405756.388 -5161 +0.744 vis 0.5 Schmidt (1875) 2406086.069 -5115 +0.296 vis 0.5 Chandler (1877) 2406143.432 -5107 +0.245 vis 0.5 Schmidt (1876) 2406143.561 -5107 +0.374 vis 0.5 Valentiner^6 (1900) 2406387.710 -5073 +0.514 vis 1 Belyavsky^7 (1910) 2406487.839 -5059 +0.168 vis 0.5 Schmidt (1877) 2406846.584 -5009 +0.077 vis 0 Schwab (1878) 2406861.175 -5007 +0.314 vis 0.5 Schmidt (1878) 2407019.283 -4985 +0.534 vis 1 Sawyer (1881) 2407212.600 -4958 +0.079 vis 0 Schwab (1879) 2407234.281 -4955 +0.230 vis 0.5 Schmidt (1879) 2407342.340 -4940 +0.638 vis 1 Schur (1895) 2407578.810 -4907 +0.276 vis 0.5 Schmidt (1880) 2407952.132 -4855 +0.407 vis 0.5 Schmidt (1881) 2408102.827 -4834 +0.391 vis 1 Schur (1895) 2408317.990 -4804 +0.252 vis 0.5 Schmidt (1882) 2408339.613 -4801 +0.345 vis 1 Sawyer (1882) 2408662.712 -4756 +0.491 vis 1 Sawyer (1883) 2408691.304 -4752 +0.376 vis 0.5 Schmidt (1883) 2409050.359 -4702 +0.594 vis 0.5 Schmidt (1884) 2409129.065 -4691 +0.356 vis 1 Schur (1895) 2410298.843 -4528 +0.326 vis 0.5 Hagen (1891) 2410873.405 -4448 +0.749 vis 0 Yendell (1889) 2411956.611 -4297 +0.268 vis 0.5 Nielsen^8 (1931) 2412315.431 -4247 +0.252 vis 0.5 Nielsen^9 (1931) 2413420.703 -4093 +0.306 vis 1 Stratonov (1904) 2413442.276 -4090. +0.349 vis 1 Plassmann (1900) 2413449.561 -4089 +0.457 vis 0.5 Sperra (1896) 2413686.167 -4056 +0.231 vis 1 Nijland (1923) 2413772.466 -4044 +0.409 vis 1 Plassmann (1900) 2413801.116 -4040 +0.352 vis 1 Stratonov (1904) 2413822.674 -4037 +0.380 vis 0.5 Sperra (1897b) 2414160.005 -3990 +0.405 vis 1 Stratonov (1904) 2414188.425 -3986 +0.118 vis 0.5 Sperra (1898) 2414188.597 -3986 +0.290 vis 1 Nijland (1923) Table 34 (cont.) Obs.Max.J.D. E O-C Type w Reference 2414195.781 -3985 +0.297d vis 1 Pickering (1904) 2414195.874 -3985 +0.390 vis 1 Plassmann (1900) 2414511.75 -3941 +0.49 vis 0.5 Grouiller^10 (1920) 2414518.830 -3940 +0.393 vis 0.5 Luizet (1903) 2414540.180 -3937 +0.213 pg 2 Schwarzschild (1900) 2414540.396 -3937 +0.429 vis 1 Plassmann (1900) 2414633.699 -3924 +0.434 vis 1 Zinner^11 (1932) 2414877.540 -3890 +0.266 vis 0.5 Luizet (1903) 2414891.843 -3888 +0.216 vis 1 Plassmann (1900) 2415222.205 -3842 +0.448 vis 0.5 Luizet (1903) 2415265.31 -3836 +0.49 vis 0.5 Grouiller^12 (1920) 2415293.886 -3832 +0.362 vis 1 Plassmann (1901) 2415408.985 -3816 +0.633 vis 0.5 Tass (1908) 2415422.993 -3814 +0.287 vis 0.5 Tass^13 (1925) 2415595.527 -3790 +0.580 vis 0.5 Kopff (1902) 2415631.188 -3785 +0.357 vis 1 Plassmann (1905) 2415631.231 -3785 +0.400 vis 0.5 Luizet (1903) 2415638.26 -3784 +0.25 vis 0.5 Grouiller^12 (1920) 2415975.731 -3737 +0.417 vis 0.5 Luizet (1903) 2415982.944 -3736 +0.453 vis 1 Plassmann (1905) 2416018.547 -3731 +0.172 vis 1 Roy, de Roy (1905) 2416169.386 -3710 +0.300 vis 1 Bilt (1924a) 2416348.694 -3685 +0.189 vis 0.5 Plassmann (1905) 2416399.103 -3678 +0.361 vis 1 Götz (1906) 2416499.422 -3664 +0.206 vis 0.5 Nielsen 14 (1931) 2416542.542 -3658 +0.266 vis 0.5 Olivier (1952) 2416671.377 -3640 -0.081 vis 0 Terkán (1905) 2416722.04 -3633 +0.35 vis 0.5 Grouiller^12 (1920) 2416736.319 -3631 +0.271 vis 1 Plassmann (1905) 2416844.019 -3616 +0.320 vis 1 Zinner^11 (1932) 2416937.329 -3603 +0.332 vis 1 Tass^13 (1925) 2416951.604 -3601 +0.254 vis 1 Bilt (1924a) 2416994.742 -3595 +0.331 vis 0.5 Schiller (1906) 2417116.659 -3578 +0.244 vis 1 Plassmann (1905, 1906) 2417123.76 -3577 +0.17 vis 0.5 Grouiller^12 (1920) 2417131.041 -3576 +0.272 vis 0.5 Furness^15 (1913) 2417339.128 -3547 +0.234 vis 1 Lohnert (1909) 2417411.5 -3537 +0.8 vis 0 Gliese^16 (1942) 2417475.556 -3528 +0.304 vis 1 Plassmann (1908) 2417497.014 -3525 +0.232 vis 0.5 Olivier (1952) 2417662.026 -3502 +0.179 pg 2 Kohlschlütter (1910) 2417748.290 -3490 +0.322 vis 1 Bilt (1924a) 2417841.751 -3477 +0.486 vis 0.5 Plassmann (1908) 2418207.341 -3426 +0.062 vis 0.5 Favaro (1909) 2418300.805 -3413 +0.229 vis 1 Lau (1908) 2418387.07 -3401 +0.37 vis 0.5 Hornig (1915) 2418552.224 -3378 +0.462 vis 0.5 Olivier (1952) 2418573.567 -3375 +0.275 vis 1 Mundler (1911) 2418860.55 -3335 +0.19 vis 0.5 Grouiller^12 (1920) 2418896.391 -3330 +0.146 vis 0.5 Becker^9 (1925) 2419004.13 -3315 +0.23 vis 0.5 Grouiller^17 (1920) 2419083.04 -3304 +0.20 vis 0.5 Grouiller^18 (1920) 2419434.858 -3255 +0.357 vis 1 Zinner^11 (1932) 2419636.08 -3227 +0.63 vis 0 Hornig (1915) 2419649.812 -3225 +0.009 vis 0.5 Breson (1913) Table 34 (cont.) Obs.Max.J.D. E O-C Type w Reference 2419678.821 -3221 +0.311d vis 1 Dziewulski (1930) 2419908.394 -3189 +0.229 vis 1 Hoffmeister (1915) 2420059.118 -3168 +0.241 vis 0.5 Olivier (1952) 2420188.362 -3150 +0.304 vis 1 Zinner^11 (1932) 2420683.572 -3081 +0.320 vis 1 Zinner^11 (1932) 2420726.441 -3075 +0.128 vis 0.5 Becker^9 (1925) 2421020.809 -3034 +0.250 vis 1 Luyten (1922) 2421429.935 -2977 +0.302 vis 1 Zinner^11 (1932) 2421444.228 -2975 +0.242 vis 0.5 Nielsen^19 (1931) 2421480.100 -2970 +0.230 vis 1 Lacchini (1921b) 2421487.176 -2969 +0.129 vis 1 Nijland (1923) 2421752.841 -2932 +0.255 vis 1 Luyten (1922) 2421788.8 -2927 +0.3 vis 0.5 Gliese^20 (1942) 2421824.507 -2922 +0.154 vis 1 Nijland (1923) 2422183.339 -2872 +0.149 vis 1 Nijland (1923) 2422233.583 -2865 +0.156 vis 0.5 Becker^9 (1925) 2422578.119 -2817 +0.209 vis 1 Nijland (1923) 2422585.217 -2816 +0.130 pe 3 Wylie (1922) 2422872.282 -2776 +0.125 vis 1 Zinner^11 (1932) 2422901.053 -2772 +0.189 vis 1 Nielsen^21 (1922) 2422908.345 -2771 +0.305 vis 1 Nijland (1923) 2422915.399 -2770 +0.182 vis 1 Zverev (1936) 2422922.433 -2769 +0.039 vis 0.5 Perepelkin (1925) 2422987.030 -2760 +0.046 vis 0.5 Nielsen^22 (1931) 2423267.112 -2721 +0.235 vis 1 Zverev (1936) 2423331.599 -2712 +0.131 vis 0.5 Becker^9 (1925) 2423331.637 -2712 +0.169 vis 1 Nielsen^21 (1929) 2423403.511 -2702 +0.276 vis 1 Parenago (1938a) 2423618.719 -2672 +0.182 vis 1 Grouiller et al:' (1932) 2423661.705 -2666 +0.108 vis 1 Hopmann (1924) 2423991.888 -2620 +0.161 pe 1 Pettit et al. (1933) 2424379.226 -2566 -0.045 vis 0.5 Parenago (1938a) 2424659.251 -2527 +0.087 pg 2 Tiercy (1930) 2424716.700 -2519 +0.122 vis 1 Kukarkin (1940) 2424731.082 -2517 +0.151 vis 1 Lipinski (1933) 2424989.329 -2481 +0.036 vis 1 Grouiller et al.^23 (1932) 2425154.388 -2458 +0.030 vis 0.5 Nielsen^9 (1931) 2425247.743 -2445 +0.087 vis 1 Collmann (1930) 2425448.768 -2417 +0.164 vis 1 Kukarkin (1940) 2425484.637 -2412 +0.149 vis 1 Parenago (1938a) 2425620.964 -2393 +0.118 vis 1 Zverev (1936) 2425663.952 -2387 +0.045 vis 1 Lipinski (1933) 2425750.158 -2375 +0.131 vis 1 McLaughlin (1934b) 2426087.426 -2328 +0.092 vis 1 Grouiller et al.^23 (1932) 2426144.825 -2320 +0.077 pe 2 Bernheimer (1931) 2426180.843 -2315 +0.212 vis 1 McLaughlin (1934b) 2426202.34 -2312 +0.18 vis 0.5 Gliese^9 (1942) 2426503.81 -2270 +0.23 vis 0.5 Gliese (1942) 2426510.767 -2269 +0.006 vis 1 Zverev (1936) 2426525.271 -2267 +0.156 vis 1 McLaughlin (1934b) 2426525.329 -2267 +0.214 vis 1 Kukarkin (1940) 2426596.873 -2257 -0.009 vis 1 Parenago (1938a) 2426747.812 -2236 +0.218 vis 1 Lipinski (1933) 2426912.889 -2213 +0.231 vis 1 McLaughlin (1934b) 2426919.965 -2212 +0.130 vis 1 Florya, Kukarkina (1953) Table 34 (cont.) Obs.Max.J.D. E O-C Type w Reference 2426998.99 -2201 +0.21d vis 0.5 Gliese (1942) 2427293.050 -2160 +0.025 vis 1 Florya, Kukarkina (1953) 2427321.85 -2156 +0.12 vis 0.5 Horn (1934) 2427601.65 -2117 +0.03 vis 0.5 Gliese^9 (1942) 2427623.348 -2114 +0.193 vis 1 Krebs (1935) 2427723.742 -2100 +0.113 vis 1 Florya (1938) 2428010.893 -2060 +0.194 vis 1 Krebs (1937) 2428047.28 -2055 +0.70 vis 0 Sures (1937) 2428297.874 -2020 +0.106 vis 0.5 Nielsen (1940) 2428427.131 -2002 +0.181 vis 1 Krebs (1937) 2429001.21 -1922 +0.12 vis 0.5 Gliese (1942) 2429101.74 -1908 +0.18 vis 0.5 Gliese^9 (1942) 2430249.903 -1748 +0.063 vis 0.5 Kappert (1942) 2430501.072 -1713 +0.046 vis 1 Nielsen (1952) 2432065.59 -1495 +0.04 vis 0.5 Pohl^24 (1951) 2432072.857 -1494 +0.126 vis 0.5 Solov'yov (1949) 2432353.20 -1455 +0.58 vis 0 Pohl^24 (1951) 2432826.427 -1389 +0.139 vis 1 Lacchini (1949) 2432840.57 -1387 -0.07 vis 0.5 Pohl (1951) 2433041.561 -1359 -0.029 pe 3 Eggen (1951) 2433070.318 -1355 +0.021 pe 3 Stebbins et al. (1952) 2433170.95 -1341 +0.18 vis 0.5 Pohl^25 (1951) 2433931.93 -1235 +0.42 vis 0 Domke, Pohl (1952) 2434240.61 -1192 +0.51 vis 0 Pohl^26 (1955) 2434599.96 -1142 +1.02 vis 0 Marks^27 (1959) 2434613.353 -1140 +0.058 pe 3 present paper^28 2434656.80 -1134 +0.44 vis 0 Pohl (1955) 2435022.70 -1083 +0.33 vis 0 Rudolph^29 (1959) 2435295.084 -1045 -0.001 pe 2 Irwin (1961) 2435574.994 -1006 +0.016 pe 2 Walraven et al. (1958) 2435725.92 -985 +0.23 vis 0.5 Rudolph^30 (1959) 2435976.91 -950 +0.04 vis 0.5 Rudolph (1959) 2436041.619 -941 +0.154 vis 1 Azarnova (1959) 2436084.514 -935 -0.012 vis 1 Vinnik (1958) 2436127.95 -929 +0.36 vis 0 Rudolph (1959) 2436141.921 -927 -0.019 pe 1 Oke (1961a) 2436809.40 -834 +0.02 vis 0.5 Braune et al.^29 (1962) 2436996.019 -808 +0.048 vis 1 Azarnova (1962) 2437153.956 -786 +0.097 vis 1 Mayall^31 (1964, 1966) 2437283.056 -768 +0.015 pe 3 Mitchell et al. (1964) 2437857.173 -688 -0.006 pe 1 Williams (1966) 2438287.635 -628 -0.148 vis 0.5 Romejko (1965) 2438926.521 -539 +0.008 pe 3 Wisniewski et al. (1968) 2439027.37 -525 +0.38 vis 0 Busch (1977b) 2439751.893 -424 +0.056 pe 2 Sudzius (1969) 2439888.148 -405 -0.047 pe 2 Schmidt (1971) 2440469.93 -324 +0.42 vis 0 Busch (1977b) 2440843.15 -272 +0.45 vis 0 Braune et al. (1972) 2440928.854 -260 +0.032 pe 3 Pel (1976) 2440957.482 -256 -0.047 pe 2 Evans (1976) 2441589.7 -168 +0.6 vis 0 Braune et al.^32 (1973) 2442794.781 0 +0.008 pe 3 present paper 2442945.512 +21 +0.028 pe 2 Dean (1977) Remarks: (observers) 1 Herschel; 2 Schwerd; 3 Heis; 4 Oudemans; 5 Winnecke; 6 Schonfeld; 7 Glasenapp; 8 Knopf; 9 Plassmann; 10 Guillaume; 11 Hartwig; 12 Markwick; 13 Terkán; 14 Balanowsky; 15 Whitney; 16 Stempell; 17 Moye; 18 Venturi; 19 Selivanov; 20 Jockisch; 21 Johansson; 22 Aurino; 23 Loreta; 24 Auzinger; 25 Menzel; 28 Born; 27 Szczepkowski; 28 Detre; 29 Pohl; 30 Masuch; 31 Evans, Lacchini, Nightingale, Orchiston, Staer, Vodrazka; 32 Pfeiffer Table 35 O-C residuals for eta Aql (median brightness) Obs.Med.J.D. E O-C Type w Reference 2404284.071 -5366 +1.576d vis 1 Valentiner^1 (1900) 2413800.226 -4040 +0.380 vis 1 Stratonov (1904) 2414539.219 -3937 +0.170 pg 2 Schwarzschild (1900) 2417661.050 -3502 +0.121 pg 2 Kohlschlütter (1910) 2422584.269 -2816 +0.100 pe 3 Wylie (1922) 2428009.917 -2060 +0.136 vis 1 Krebs (1937) 2430500.103 -1713 -0.005 vis 1 Nielsen (1952) 2433040.657 -1359 -0.015 pe 3 Eggen (1951) 2433069.399 -1355 +0.020 pe 3 Stebbins et al. (1952) 2438925.610 -539 +0.015 pe 3 Wisniewski et al. (1968) 2440927.943 -260 +0.039 pe 3 Pel (1976) 2442793.834 0 -0.021 pe 3 present paper Remark: 1 Observer: Schonfeld V 600 Aquilae The light and colour curves of V 600 Aql are plotted in Fig. 53. The O-C residuals have been computed with the formula: C = 2442904.119 + 7.238748d*E
Figure 53 B and B-V curves of V 600 Aql If the first two points in the O-C diagram (Table 36) are reliable, a period change must have occurred during an epoch before J.D. 2428000. Unfortunately, neither the epoch of the period change nor the former value of the period can be determined.
Figure 54 O-C diagram of V 600 Aql Table 36 O-C residuals for V 600 Aql Obs.Max.J.D. E O-C Type w Reference 2415224.4 -3824 +1.3d pg 0.5 Tsessevich (1946) 2418924.2 -3313 +2.1 pg 0.5 Tsessevich (1946) 2428752.309 -1955 -0.058 pg 1 Kurochkin (1948) 2428773.9 -1952 -0.2 pg 0.5 Tsessevich (1946) 2429490.9 -1853 +0.2 pg 0.5 Tsessevich (1946) 2431336.72 -1598 +0.12 vis 0.5 Tsessevich (1946) 2431670.42 -1552 +0.84 vis 0 Tsessevich (1946) 2435622.024 -1006 +0.085 pe 3 Walraven et al. (1958) 2436707.675 -856 -0.076 pg 1 Chupilko (1961) 2436838.235 -838 +0.187 vis 0.5 Voigtlander (1964) 2437453.264 -753 -0.078 pe 2 Mitchell et al. (1964) 2437960.293 -683 +0.239 vis 0.5 Voigtlander (1964) 2440877.304 -280 +0.034 pe 3 Pel (1976) 2442904.092 0 -0.027 pe 3 present paper V 336 Aquilae The B-V amplitude of this Cepheid is smaller (see Fig. 55) than was determined by Schaltenbrand and Tammann (1971). This is likely to result from the one-sided deviation of the data points from the normal curve (due to the scatter) which tends to decrease the amplitude in this particular case. Table 37 O-C residuals for V 336 Aql Obs.Max.J.D. E O-C Type w Reference 2414870.38 -3858 +0.90d pg 0 Kurochkin (1958) 2427600.31 -2115 0.00 vis 0.5 Selivanov (1935) 2427651.60 -2108 +0.17 pg 0.5 Harwood (1938) 2427826.901 -2084 +0.171 vis 1 Beyer (1936) 2429842.588 -1808 -0.039 pg 1 Solov'yov (1948) 2429908.428 -1799 +0.065 pg 1 Kapko (1963) 2430777.427 -1680 -0.109 pg 1 Kapko (1963) 2431266.830 -1613 -0.073 pg 1 Solov'yov (1948) 2433078.301 -1365 +0.012 pg 1 Filatov (1961) Table 37 (cont.) Obs.Max.J.D. E O-C Type w Reference 2433187.854 -1350 +0.006d pg 1 Kurochkin (1958) 2433867.048 -1257 -0.070 pg 1 Filatov (1961) 2434400.317 -1184 +0.009 pg 1 Filatov (1961) 2434546.235 -1164 -0.153 pg 1 Kapko (1963) 2435364.444 -1052 +0.011 pe 2 Walraven et al. (1958) 2435525.042 -1030 -0.079 pg 1 Filatov (1961) 2435758.924 -998 +0.076 pe 3 Weaver et al. (1960) 2437285.337 -789 -0.042 pe 2 Mitchell et al. (1964) 2437577.17 -749 -0.37 pg 0 Jetschke (1969) 2437869.46 -709 -0.24 pg 0.5 Jetschke (1969) 2438322.12 -647 -0.42 pg 0 Jetschke (1969) 2438614.43 -607 -0.27 pg 0.5 Jetschke (1969) 2438936.50 -563 +0.42 pg 0 Jetschke (1969) 2439286.33 -515 -0.34 pg 0 Jetschke (1969) 2439593.01 -473 -0.43 pg 0 Jetschke (1969) 2440842.452 -302 +0.037 pe 3 Pel (1976) 2443048.212 0 -0.004 pe 3 present paper
Figure 55 B and B-V curves of V 336 Aql The O-C residuals have been derived using the formula: C = 2443048.216 + 7.303976d*E The O-C diagram in Fig. 56 shows a constant period thus the possible period variation reported in the G.C.V.S. (Kukarkin et al. 1969-1970) cannot be confirmed.
Figure 56 O-C diagram of V 336 Aql BB Herculis The classification of this variable is doubtful. The large radial velocity suggests its belonging to Population II (CW group) (2nd Suppl. to the G.C.V.S.; Kukarkin et al. 1974), but the light and colour curves (see Fig. 57) are common for a Population I or classical Cepheid. The variable has a faint companion within the edge of the diaphragm.
Figure 57 B and B-V curves of BB Her The O-C residuals have been computed with the formula: C = 2442679.289 + 7.507945d*E The O-C diagram in Fig. 58 shows one change in the period: before J.D. 2430700 P = 7.507696d , after J.D. 2430700 P = 7.507945d . Table 38 O-C residuals for BB Her Obs.Max.J.D. E O-C Type w Reference 2418924.548 -3164 +0.397d pg 1 Parenago (1934a) 2424780.209 -2384 -0.139 pg 0.5 Albitzky (1928) 2425869.158 -2239 +0.158 vis 1 Kukarkin (1940) 2425884.218 -2237 +0.202 vis 1 Jacchia (1930) 2426034.278 -2217 +0.103 pg 1 Lassovszky (1931) 2426184.488 -2197 +0.154 vis 1 Jacchia (1930) 2429818.197 -1713 +0.018 pg 1 Mergentaler (1948) 2430546.475 -1616 +0.025 pg 1 Mergentaler (1948) 2433121.605 -1273 -0.070 pe 3 Eggen et al. (1957) 2433279.360 -1252 +0.018 pg 1 Solov'yov (1957) 2433542.091 -1217 -0.029 pg 1 Fridel' (1961) 2434037.752 -1151 +0.108 pg 1 Koval' (1957) 2434045.140 -1150 -0.012 pg 1 Solov'yov (1957) 2434600.745 -1076 +0.005 pg 1 Solov'yov (1957) 2434961.220 -1028 +0.098 pg 1 Solov'yov (1957) 2435344.023 -977 -0.004 pg 1 Solov'yov (1957) 2435449,141 -963 +0.003 pe 2 Walraven et al. (1958) 2435644.263 -937 -0.082 pg 1 Fridel' (1961) 2435696.87 -930 -0.03 pg 0.5 Vasil'yan. et al. (1970) 2436057.23 -882 -0.05 pg 0.5 Vasil'yan. et al. (1970) 2436417.58 -834 -0.08 pg 0.5 Vasil'yan. et al. (1970) 2436492.614 -824 -0.128 pg 1 Fridel' (1961) 2436793.03 -784 -0.03 pg 0.5 Vasil'yan. et al. (1970) 2437160.81 -735 -0.14 pg 0.5 Vasil'yan. et al. (1970) 2437296.203 -717 +0.111 pe 3 Mitchell et al. (1964) 2437551.38 -683 +0.02 pg 0.5 Vasil'yan. et al. (1970) 2437829.164 -646 +0.007 pe 3 Michal.-Smak et al. (1965) 2437866.66 -641 -0.04 pg 0.5 Vasil'yan. et al. (1970) 2438227.088 -593 +0.010 pe 3 Kwee, Braun (1967) 2438257.20 -589 +0.09 pg 0.5 Vasil'yan. et al. (1970) 2438594.95 -544 -0.02 pg 0.5 Vasil'yan. et al. (1970) 2442679.245 0 -0.044 pe 3 present paper
Figure 58 O-C diagram of BB Her HR 690 This recently discovered Cepheid (Henriksson 1977) in constellation Perseus has extremely low amplitudes (see Fig. 59). It would be very important to know whether this variable is a physical member of the h and X Persei but as far as the photoelectric V magnitudes allow one to draw a conclusion, HR 690 would be overluminous at the distance of the above-mentioned clusters, i.e. its belonging to either cluster is doubtful.
Figure 59 B, B-V and U-B curves of HR 690 The O-C diagram of HR 690 cannot be constructed because no other observations are available. Unfortunately, Henriksson's (1977) observations - which might well be useful in refining the period - have remained unpublished. Using only the present photometric data, however, I determined a slightly shorter period: 7.552 instead of the value 7.572 given by Henriksson. RS Orionis The light and colour curves of this Cepheid are shown in Fig. 60. The variable has a B6 photometric companion (Madore 1977). The O-C residuals have been computed using the ephemeris: C = 2442820.800 + 7.566881d*E Table 39 O-C residuals for RS Ori Obs.Max.J.D. E O-C Type w Reference 2416533.795 -3474 +0.340d pg 1 Kukarkina (1955) 2418274.055 -3244 +0.217 vis 1 Munch (1909) 2418381.4 -3230 +1.6 vis 0 Luizet (1913) 2419045.912 -3142 +0.252 pg 0.5 Robinson (1933) 2419098.7 -3135 +0.1 vis 0.5 Luizet (1913) 2419514.995 -3080 +0.188 pg 0.5 Hertzsprung (1928) 2419743.4 -3050 +1.6 vis 0 Zinner (1913) 2421936.353 -2760 +0.145 pg 1 Jordan (1929) 2424879.918 -2371 +0.193 vis 1 Rybka (1930)
Figure 60 B, B-V and U-B curves of RS Ori Table 39 (cont.) Obs.Max.J.D. E O-C Type w Reference 2425235.626 -2324 +0.257d vis 1 Rybka (1930) 2425326.322 -2312 +0.151 pg 1 Puchinskas (1962) 2425522.87 -2286 -0.04 pg 0.5 Martynov (1948) 2426393.242 -2171 +0.141 pg 1 Martynov (1951) 2427233.264 -2060 +0.239 pg 1 Martynov (1951) 2427581.209 -2014 +0.107 pg 1 Puchinskas (1962) 2427982.333 -1961 +0.187 pg 1 Martynov (1951) 2428565.060 -1884 +0.264 pg 1 Martynov (1951) 2429064.379 -1818 +0.169 pg 1 Martynov (1951) 2429306.578 -1786 +0.227 pg 1 Koshkina (1963) 2429798.322 -1721 +0.124 pg 1 Martynov (1951) 2430305.180 -1654 +0.001 vis 0.5 Kukarkina^1 (1955) 2430751.793 -1595 +0.168 pg 1 Martynov (1951) 2431039.385 -1557 +0.219 pg 1 Kukarkina (1955) 2433892.019 -1180 +0.139 pg 1 Koshkina (1963) 2433960.037 -1171 +0.055 pg 1 Solov'yov (1956) 2435178.286 -1010 +0.036 pe 2 Irwin (1961) 2435208.500 -1006 -0.018 pe 2 Walraven et al. (1958) 2436192.193 -876 -0.019 pe 3 Bahner et al. (1977) 2436282.987 -864 -0.028 pg 1 Puchinskas (1962) 2436608.377 -821 -0.014 pg 0.5 Huth (1963) Table 39 (cont.) Obs.Max.J.D. E O-C Type w Reference 2436835.395 -791 -0.002d pe 3 Weaver et al. (1960) 2437047.280 -763 +0.010 pe 3 Mitchell et al. (1964) 2437599.63 -690 -0.02 pg 0.5 Ahnert (1964) 2438076.401 -627 +0.035 p9 1 Fridel' (1971) 2440777.748 -270 +0.006 pe 3 Pel (1976) 2442820.794 0 -0.006 pe 3 present paper Remark: 1 Observer: Lasebnik The O-C diagram in Fig. 61 can be approximated by two almost parallel lines showing the phenomenon of the rejumping period. Both the period jump and the subsequent rejump occurred between J.D. 2433000 and J.D. 2435000. The values of the period during the other intervals are as follows: before J.D. 2433000 P = 7.566836d , after J.D. 2435000 P = 7.566881d .
Figure 61 O-C diagram of RS Ori GH Cygni
Figure 62 B and B-V curves of GH Cyg The light and colour curves of this Cepheid variable are shown in Fig. 62. In order to obtain a precise value of the period I was obliged to take into account also the normal maxima with 0.5 weight when fitting a line to the points in the O-C diagram (Fig. 63). The O-C residuals have been computed with the formula: C = 2442743.743 + 7.817930d*E The period has been constant since the discovery of GH Cyg's light variation.
Figure 63 O-C diagram of GH Cyg Table 40 O-C residuals for GH Cyg Obs.Max.J.D. E O-C Type w Reference 2415310.606 -3509 -0.021d pg 0.5 Parenago (1934b) 2420376.64 -2861 0.00 pg 0.5 Oosterhoff (1935) 2421877.56 -2669 -0.13 pg 0.5 Oosterhoff (1935) 2424755.18 -2301 +0.49 pg 0 Oosterhoff (1935) 2425074.93 -2260 -0.29 pg 0.5 Oosterhoff (1935) 2425528.56 -2202 -0.10 pg 0.5 Oosterhoff (1935) 2425778.30 -2170 -0.53 pg 0 Oosterhoff (1935) 2426130.66 -2125 +0.02 pg 0.5 Nassau, Ashbrook (1942) 2426138.4 -2124 -0.1 pg 0.5 Schneller (1930) 2426231.62 -2112 -0.65 pg 0 Oosterhoff (1935) 2426943.52 -2021 -0.19 pg 0.5 Oosterhoff (1935) 2427600.36 -1937 -0.05 pg 0.5 Nassau, Ashbrook (1942) 2428351.01 -1841 +0.08 pg 0.5 Nassau, Ashbrook (1942) 2428429.36 -1831 +0.25 pg 0.5 Wachmann (1963) 2428804.45 -1783 +0.08 pg 0.5 Wachmann (1963) 2429179.58 -1735 -0.05 pg 0.5 Parenago (1946) 2429195.37 -1733 +0.10 pg 0.5 Wachmann (1963) 2430094.24 -1618 -0.09 vis 0.5 Ashbrook (1943) 2430641.798 -1548 +0.211 pg 0.5 Solov'yov (1944) 2432525.850 -1307 +0.142 pg 1 Duncombe (1949) 2432838.40 -1267 -0.03 pg 0.5 Wachmann (1963) 2433456.435 -1188 +0.393 pg 0 Satyvaldiev (1966) 2433792.262 -1145 +0.049 pg 0.5 Chuprina (1953) 2433878.11 -1134 -0.10 pg 0.5 Wachmann (1963) 2433878.384 -1134 +0.174 pg 0.5 Shteiman (1958) 2434535.052 -1050 +0.136 pg 0.5 Satyvaldiev (1966) 2434714.71 -1027 -0.02 pg 0.5 Wachmann (1963) 2434972.629 -994 -0.092 pg 0.5 Satyvaldiev (1966) 2435222.991 -962 +0.097 pg 0.5 Shteiman (1958) Table 40 (cont.) Obs.Max.J.D. E O-C Type w Reference 2435363.542 -944 -0.075d pe 2 Walraven et al. (1958) 2435426.30 -936 +0.14 pg 0.5 Wachmann (1963) 2435676.517 -904 +0.183 pg 0.5 Satyvaldiev (1966) 2435700.03 -901 +0.24 pg 0.5 Huth (1966) 2436051.45 -856 -0.14 pg 0.5 Huth (1966) 2436403.48 -811 +0.08 pg 0.5 Huth (1966) 2436607.157 -785 +0.489 pg 0 Satyvaldiev (1966) 2436802.097 -760 -0.019 pe 3 Oosterhoff (1960) 2436802.152 -760 +0.036 pe 3 Weaver et al. (1960) 2436810.64 -759 +0.71 pg 0 Huth (1966) 2436825.433 -757 -0.137 vis 0.5 Voigtlander (1964) 2437044.54 -729 +0.07 pg 0.5 Huth (1966) 2437513.78 -669 +0.23 pg 0.5 Huth (1966) 2437607.641 -657 +0.278 pg 0 Satyvaldiev (1966) 2437849.630 -626 -0.089 pe 1 Eggen (1969) 2437936.10 -615 +0.38 pg 0 Huth (1966) 2437959.340 -612 +0.170 vis 0.5 Voigtlander (1964) 2438170.72 -585 +0.47 pg 0 Huth (1966) 2438584.27 -532 -0.33 pg 0 Huth (1966) 2442743.705 0 -0.038 pe 3 present paper VY Cygni The amplitudes of both the light and the colour variations (see Fig. 64) are smaller than given by Schaltenbrand and Tammann (1971). Moreover, the descending branch of the light curve
Figure 64 B and B-V curves of VY Cyg
differs from that given by Nikolov (1968). The variable has a B7 photometric companion
(Madore 1977).
The O-C residuals listed in Tables 41 and 42 have been calculated using the formulae:
C_{max} = 2443045.282 + 7.856982d*E ,
C_{med} = 2443044.388 + 7.856982d*E ,
for the moments of the maximum and the median brightness, respectively. The O-C diagram in
Fig. 65 shows the constancy of the period.
Figure 65 O-C diagram of VY Cyg Table 41 O-C residuals for VY Cyg (maximum brightness) Obs.Max.J.D. E O-C Type w Reference 2415294.491 -3532 +0.069d pg 1 Kulikovsky (1932) 2415341.349 -3526 -0.214 pg 0.5 Williams (1904) 2416394.354 -3392 -0.045 vis 1 Williams (1904) 2417400.122 -3264 +0.029 vis 1 Luizet (1907c) 2417424.070 -3261 +0.406 vis 0 Seares (1907a) 2417832.286 -3209 +0.059 vis 1 Zeipel (1908) 2420660.780 -2849 +0.040 vis 0.5 Doberck (1920a) 2421572.265 -2733 +0.115 vis 0.5 Doberck (1920a) 2422169.260 -2657 -0.021 vis 0.5 Doberck (1920a) 2423120.061 -2536 +0.085 pg 1 Henroteau (1924) 2423308.463 -2512 -0.080 vis 0.5 Doberck (1924c) 2423701.287 -2462 -0.105 vis 0.5 Doberck (1924c) 2425759.910 -2200 -0.012 pg 2 Oosterhoff (1933) 2425964.191 -2174 -0.012 vis 1 Lassovszky (1933) 2426396.299 -2119 -0.038 pg 2 Oosterhoff (1933) 2426836.359 -2063 +0.031 vis 1 Lassovszky (1933) 2426946.34 -2049 +0.01 vis 0.5 Miczaika (1936) 2428973.422 -1791 -0.005 pg 0.5 Shnirelman (1940) 2429036.39 -1783 +0.11 vis 0.5 Krebs (1939) 2430953.276 -1539 -0.111 pg 1 Solov'yov (1957) 2431817.470 -1429 -0.185 pg 1 Solov'yov (1957) 2432791.897 -1305 -0.023 pg 1 Solov'yov 0957) 2433169.085 -1257 +0.029 pg 1 Solov'yov (1957) 2433883.966 -1166 -0.075 pg 1 Shteiman (1958) Table 41 (cont.) Obs.Max.J.D. E O-C Type w Reference 2434143.395 -1133 +0.074d pg 1 Solov'yov (1957) 2434536.164 -1083 -0.006 pg 1 Shteiman (1958) 2435667.557 -939 -0.019 pg 1 Shteiman (1958) 2436092.883 -885 +1.030 pg 0 Korovkina (1958) 2436445.50 -840 +0.08 pg 0.5 Korovkina (1959) 2436775.410 -798 0.000 pe 3 Weaver et al. (1960) 2436806.815 -794 -0.023 pe 3 Oosterhoff (1960) 2437223.217 -741 -0.041 pe 2 Mitchell et al. (1964) 2438229.017 -613 +0.065 pe 3 Kwee, Braun (1967) 2438229.056 -613 +0.104 pg 1 Girnyak (1971) 2439297.405 -477 -0.097 pg 1 Girnyak (1971) 2443045.328 0 +0.046 pe 3 present paper Table 42 O-C residuals for VY Cyg (median brightness) Obs.Med.J.D. E O-C Type w Reference 2425758.983 -2200 -0.045d pg 2 Oosterhoff (1933) 2426395.396 -2119 -0.047 pg 2 Oosterhoff (1933) 2436805.966 -794 +0.022 pe 3 Oosterhoff (1960) 2438228.074 -613 +0.014 pe 3 Kwee, Braun (1967) 2443044.424 0 +0.036 pe 3 present paper RX Camelopardalis
Figure 66 B, B-V and U-B curves of RX Cam
The amplitude of the light curve in the B band plotted in Fig. 66 as well as that of
the V light curve is smaller than the corresponding value given by Schaltenbrand and Tammann
(1971). The O-C diagrams could be constructed for both the maximum and the median
brightnesses. The O-C residuals have been calculated by the formulae:
C_{max} = 2442766.583 + 7.912024d*E ,
C_{med} = 2442765.524 + 7.912024d*E .
The Cepheid RX Cam has a constant period (see Fig. 67) but a long term wave-like variation
can be suspected as if RX Cam were a member of a binary system. In the absence of definite
evidence (e.g. spectroscopic or photometric), it cannot be stated that this variable is
really a component of a binary system.
Figure 67 O-C diagram of RX Cam Table 43 O-C residuals for RX Cam (maximum brightness) Obs.Max.J.D. E O-C Type w Reference 2419441.807 -2948 -0.129d pg 1 Hertzsprung (1928) 2420359.763 -2832 +0.032 pg 0.5 Robinson (1933) 2422456.523 -2567 +0.106 vis 0.5 Zakharov (1952) 2422638.293 -2544 -0.101 vis 1 Doberck (1924a) 2422970.715 -2502 +0.016 vis 0.5 Zakharov (1952) 2423311.080 -2459 +0.164 vis 1 Zakharov (1952) 2424054.759 -2365 +0.113 vis 1 Zakharov (1952) 2424394.871 -2322 +0.008 vis 1 Zakharov (1952) 2424774.677 -2274 +0.037 vis 1 Zakharov (1952) 2425138.644 -2228 +0.050 vis 1 Zakharov (1952) 2425431.419 -2191 +0.081 vis 1 Zakharov (1952) 2425874.434 -2135 +0.022 vis 1 Zakharov (1952) 2426198.881 -2094 +0.076 vis 1 Zakharov (1952) 2426926.719 -2002 +0.008 vis 1 Florya, Kukarkina (1953) 2427124.574 -1977 +0.062 vis 0.5 Dziewulski et al. (1946) 2427290.599 -1956 -0.065 vis 1 Florya, Kukarkina (1953) 2427899.933 -1879 +0.043 vis 0.5 Dziewulski (1947) Table 43 (cont.) Obs.Max.J.D. E O-C Type w Reference 2428184.795 -1843 +0.072d vis 1 Krebs (1937) 2428524.867 -1800 -0.073 vis 1 Krebs (1937) 2428580.028 -1793 -0.296 pg 0.5 Dziewulski et al. (1946) 2432947.647 -1241 -0.114 pe 3 Eggen (1951) 2435795.998 -881 -0.092 pe 2 Prokof'yeva (1961) 2436824.745 -751 +0.092 pe 2 Weaver et al. (1960) 2436903.754 -741 -0.019 pe 3 Bahner et al. (1962) 2437251.794 -697 -0.108 pe 1 Mitchell et al. (1964) 2437963.959 -607 -0.025 pe 1 Williams (1966) 2438739.388 -509 +0.025 pe 1 Haug (1970) 2439040.043 -471 +0.023 pe 3 Wamsteker (1972) 2442766.639 0 +0.056 pe 3 present paper Table 44 O-C residuals for RX Cam (median brightness) Obs.Med.J.D. E O-C Type w Reference 2419440.747 -2948 -0.130d pg 1 Hertzsprung (1928) 2436902.670 -741 -0.044 pe 3 Bahner et al. (1962) 2439039.006 -471 +0.045 pe 3 Wamsteker (1972) 2442765.587 0 +0.063 pe 3 present paper W Geminorum
Figure 68 B, B-V and U-B curves of W Gem The light and colour curves of this Cepheid are shown in Fig. 68. The O-C residuals have been computed with the formula: C = 2442755.191 + 7.913779d*E The O-C diagram in Fig. 69 shows one change in the period: before J.D. 2431700 P = 7.914553d , after J.D. 2431700 P = 7.913779d .
Figure 69 O-C diagram of W Gem Table 45 O-C residuals for W Gem Obs.Max.J.D. E O-C Type w Reference 2413267.28 -3726 -1.17d vis 0 Sawyer (1897) 2413630.627 -3680 -1.857 vis 0.5 Luizet (1905b) 2413655.4 -3677 -0.8 vis 0 Yendell (1897a) 2413860.034 -3651 -1.950 vis 0.5 Sperra (1897a) 2414136.862 -3616 -2.104 vis 1 Pickering (1904) 2414738.835 -3540 -1.578 vis 0 Luizet (1905b) 2415047.336 -3501 -1.715 vis 0:5 Luizet (1905b) 2415736.261 -3414 -1.288 vis 0.5 Luizet (1905b) 2415776.092 -3409 -1.026 vis 0 Yendell (1902) 2416155.892 -3361 -1.088 vis 0 Luizet (1905b) 2416503.868 -3317 -1.318 vis 0.5 Luizet (1905b) 2416535.714 -3313 -1.127 vis 0.5 Lau (1906) 2416867.736 -3271 -1.484 vis 0.5 Luizet (1905b) 2417318.675 -3214 -1.630 vis 1 Wendell (1913) 2417659.022 -3171 -1.576 vis 1 Zeipel (1908) 2417944.327 -3135 -1.167 vis 1 Bilt (1926a) 2418324.126 -3087 -1.229 vis 1 Bilt (1926a) 2418807.014 -3026 -1.082 vis 1 Bilt (1926a) 2419518.936 -2936 -1.400 pg 0.5 Hertzsprung (1928) 2419748.851 -2907 -0.984 vis 1 Bilt (1926a) 2420073.25 -2866 -1.05 vis 0.5 Dziewulski (1924) 2420682.567 -2789 -1.094 pg 0.5 Robinson (1933) 2423421.284 -2443 -0.545 vis 0.5 Doberck (1924b) 2424980.146 -2246 -0.697 pg 1 Carrasco (1932) Table 45 (cont.) Obs.Max.J.D. E O-C Type w Reference 2425296.648 -2206 -0.747d pg 2 Hellerich (1935) 2425297.250 -2206 -0.145 vis 0 Kukarkin (1940) 2425305.01 -2205 -0.30 vis 0.5 Lause (1937) 2425716.263 -2153 -0.562 vis 1 Zverev (1936) 2426421.135 -2064 -0.016 pg 0 Ahnert (1951) 2426578.991 -2044 -0.436 vis 1 Zverev (1936) 2426666.149 -2033 -0.329 vis 1 Kukarkin (1940) 2426895.429 -2004 -0.549 pg 1 Kox (1935) 2427030.096 -1987 -0.416 vis 1 Florya, Kukarkina (1953) 2427592.11 -1916 -0.28 vis 0.5 Krebs (1940) 2427885.162 -1879 -0.038 pg 0 Ahnert (1951) 2429364.701 -1692 -0.376 pg 1 Koshkina (1963) 2430022.041 -1609 +0.120 pg 0 Ahnert (1951) 2431026.850 -1482 -0.121 pg 0.5 Ahnert (1951) 2433749.626 -1138 +0.318 pg 0 Koshkina (1963) 2434746.32 -1012 -0.13 vis 0.5 Marks (1959) 2435023.68 -977 +0.25 vis 0.5 Marks^1 (1959) 2435165.909 -959 +0.032 pe 1 Irwin (1961) 2435561.781 -909 +0.215 pg 1 Nikulina (1959) 2435569.363 -908 -0.117 pe 2 Walraven et al. (1958) 2436186.729 -830 -0.025 vis 1 Latyshev (1969) 2437270.925 -693 -0.017 pe 3 Mitchell et al. (1964) 2437927.814 -610 +0.028 pg 1 Fridel' (1971) 2439043.666 -469 +0.037 pe 3 Wisniewski et al. (1968) 2439083.150 -464 -0.048 pe 3 Takase (1969) 2439502.615 -411 -0.013 pe 3 Wamsteker (1972) 2439787.563 -375 +0.039 pe 3 present paper^2 2440927.150 -231 +0.042 pe 3 Pel (1976) 2441006.204 -221 -0.042 pe 2 Evans (1976) 2442296.312 -58 +0.120 pg 0.5 Berdnikov (1977) 2442755.172 0 -0.019 pe 3 present paper Remarks: 1 Observer: Wroblewski; 2 Observer: Abaffy U Vulpeculae The light and colour curves of this variable are plotted in Fig. 70. The period of this Cepheid is very close to eight days, thus a reliable light curve can only be obtained during a time interval longer than one observing season. The lack of the complete light curve was the reason for the epoch of the minimum brightness being given in the G.C.V.S. (Kukarkin et al. 19691970) instead of that of the light maximum. The O-C residuals have been derived using the formula: C = 2442526.290 + 7.990629d*E The period of this variable has been constant since the discovery of its light variation.
Figure 70 B, B-V and U-B curves of U Vul
Figure 71 O-C diagram of U Vul Table 46 O-C residuals for U Vul Obs.Max.J.D. E O-C Type w Reference 2414215.610 -3543 +0.119d vis 1 Muller, Kempf (1898) 2414582.950 -3497 -0.110 vis 1 Wendell (1909) 2414583.509 -3497 +0.449 vis 0.5 Luizet (1899) 2414854.90 -3463 +0.16 vis 0.5 Luizet (1907a) 2414894.60 -3458 -0.09 vis 0.5 Yendell (1901) 2415158.294 -3425 -0.092 vis 1 Zinner^1 (1932) 2415206.95 -3419 +0.62 vis 0 Luizet (1907a) 2415333.31 -3403 -0.87 vis 0 Yendell (1901) 2415574.19 -3373 +0.29 vis 0.5 Luizet (1907a) 2415911.703 -3331 +2.198 vis 0 Prittwitz (1907) 2415940.04 -3327 -1.43 vis 0 Yendell (1904) Table 46 (cont.) Obs.Max.J.D. E O-C Type w Reference 2415949.75 -3326 +0.29d vis 0.5 Luizet (1907a) 2416317.32 -3280 +0.29 vis 0.5 Luizet (1907a) 2416716.65 -3230 +0.09 vis 0.5 Luizet (1907a) 2417036.62 -3190 +0.44 vis 0.5 Luizet (1907a) 2417060.091 -3187 -0.064 pg 1 Wilkens (1906) 2417411.91 -3143 +0.17 vis 0.5 Luizet (1907a) 2417436.36 -3140 +0.65 vis 0 Bemporad (1908) 2417483.1 -3134 -0.6 pg 0 Seares (1907a) 2417883.370 -3084 +0.180 vis 1 Zeipel (1908) 2418082.962 -3059 +0.006 vis 1 Bilt (1926c) 2418610.266 -2993 -0.071 vis 1 Bilt (1926c) 2418954.481 -2950 +0.547 vis 0 Jost (1913) 2419657.029 -2862 -0.081 vis 1 Bilt (1926c) 2420400.228 -2769 -0.010 pg 0.5 Robinson (1933) 2423212.920 -2417 -0.020 vis 1 Doberck (1925) 2425202.6 -2168 0.0 vis 0.5 Lause (1937) 2425498.277 -2131 +0.017 vis 1 Kukarkin (1940) 2425761.777 -2098 -0.173 vis 1 Parenago (1938a) 2426121.709 -2053 +0.180 vis 1 Zverev (1936) 2426553.206 -1999 +0.183 vis 1 Kukarkin (1940) 2426864.635 -1960 -0.022 pg 1 Kox (1935) 2426928.536 -1952 -0.046 vis 1 Florya, Kukarkina (1953) 2428215.011 -1791 -0.062 vis 1 Krebs (1937) 2428454.835 -1761 +0.043 vis 1 Kepinski (1937) 2430308.944 -1529 +0.326 vis 0.5 Model, Lochel (1964) 2430638.38 -1488 +2.15 vis 0 Stein (1944) 2430956.020 -1448 +0.161 vis 0.5 Model, Lochel (1964) 2433480.40 -1132 -0.50 vis 0 Domke, Pohl^2 (1952) 2433704.781 -1104 +0.145 pg 1 Chuprina (1952) 2434591.618 -993 +0.023 pe 3 present paper^3 2435638.397 -862 +0.029 pe 3 Walraven et al. (1958) -2435694.12 -855 -0.18 pg 0.5 Huth (1966) 2436053.22 -810 -0.66 pg 0 Huth (1966) 2436125.772 -801 -0.024 pe 3 Bahner et al. (1971) 2436436.77 -762 -0.66 pg 0 Huth (1966) 2436724.99 -726 -0.10 pg 0.5 Huth (1966) 2436781.008 -719 -0.020 pe 3 Weaver et al. (1960) 2436812.9 -715 -0.1 vis 0.5 Haussler (1964a) 2437172.15 -670 -0.42 pg 0 Huth (1966) 2437244.483 -661 -0.001 pe 3 Mitchell et al. (1964) 2437579.84 -619 -0.25 pg 0.5 Huth (1966) 2437580.0 -619 -0.1 vis 0.5 Haussler (1964a) 2437827.47 -588 -0.33 pg 0 Huth (1966) 2438235.1 -537 -0.2 vis 0.5 Haussler (1964a) 2438243.06 -536 -0.25 pg 0.5 Huth (1966) 2438642.60 -486 -0.24 pg 0.5 Huth (1966) 2440121.046 -301 -0.065 pe 3 Asteriadis et al. (1977) 2440840.247 -211 -0.020 pe 3 Evans (1976) 2442526.328 0 +0.038 pe 3 present paper Remarks: 1 Observer: Hartwig 2 Obs.: Mielke 3 Obs.: Detre DL Cassiopeiae The amplitude of the light and colour curves shown in Fig. 72 are smaller than would be expected from the catalogue compiled by Schaltenbrand and Tammann (1971). The Cepheid DL Cas is a member of the open cluster NGC 129 (Arp et al. 1959).
Figure 72 B, B-V and U-B curves of DL Cas
Figure 73 O-C diagram of DL Cas The O-C residuals have been computed with the ephemeris: C = 2442780.334 + 8.000669d*E Although DL Cas was reported as having a changing period (Hoffleit 1971, Briggs 1978), the O-C diagram in Fig. 73 does not confirm the variability in the period. Table 47 O-C residuals for DL Cas Obs.Max.J.D. E O-C Type w Reference 2426163.82 -2077 +0.88d pg 0 Kiehl, Hopp (1977) 2428059.42 -1840 +0.32 pg 0.5 Ahnert et al. (1943) 2428564.53 -1777 +1.39 pg 0 Ahnert et al. (1943) 2429131.3 -1706 +0.1 pg 0.5 Meshkova (1940) 2429467.44 -1664 +0.22 pg 0.5 Ahnert et al. (1943) 2429851.5 -1616 +0.2 vis 0.5 Loreta (1940) 2430307.13 -1559 -0.16 pg 0.5 Solov'yov (1943) 2430611.22 -1521 -0.10 pg 0.5 Solov'yov (1943) 2430979.26 -1475 -0.09 pg 0.5 Solov'yov (1943) 2434148.0 -1079 +0.4 vis 0.5 Gunther (1954) 2435107.24 -959 -0.45 pg 0.5 Romano (1959) 2435435.29 -918 -0.42 pg 0.5 Romano (1959) 2435675.42 -888 -0.32 pg 0.5 Romano (1959) 2435835.880 -868 +0.13 pg 0.5 Zonn, Wroblewski (1964) 2436163.768 -827 -0.013 pe 3 Arp et al. (1959) 2436803.942 -747 +0.108 pe 3 Oosterhoff (1960) 2437220.052 -695 +0.183 pe 2 Mitchell et al. (1964) 2437947.988 -604 +0.058 pe 2 Williams (1966) 2438708.126 -509 +0.133 pe 2 Haug (1970) 2439043.481 -467 -0.541 vis 0 Haussler et al. (1973) 2439411.494 -421 -0.558 vis 0 Haussler et al. (1973) 2440483.510 -287 -0.632 vis 0 Haussler et al. (1973) 2442068.04 -89 -0.23 vis 0.5 Small (1974) 2442780.311 0 -0.023 pe 3 present paper BK Aurigae The light and colour curves of this variable are shown in Fig. 74. The O-C residuals have been calculated using the formula: C = 2442825.384 + 8.002432d*E The period of BK Aur has been constant since the discovery of this star's light variation. Table 48 O-C residuals for BK Aur Obs.Max.J.D. E O-C Type w Reference 2417249.593 -3196 -0.18d pg 1 Kukarkin (1949) 2419002.198 -2977 +0.054 pg 0.5 Ashbrook (1943) 2422699.065 -2515 -0.203 pg 0.5 Ashbrook (1943) 2425499.929 -2165 -0.190 pg 0.5 Ashbrook (1943) 2428396.826 -1803 -0.173 pg 0.5 Ashbrook (1943) 2428525.249 -1787 +0.211 vis 1 Kukarkin (1949) 2428564.95 -1782 -0.10 pg 0.5 Richter (1973) 2428621.20 -1775 +0.13 vis 0.5 Kukarkin^1 (1949) 2428629.154 -1774 +0.084 pg 1 Kukarkin (1949) 2431021.64 -1475 -0.16 pg 0.5 Richter (1973) 2432614.48 -1276 +0.20 pg 0.5 Richter (1973) 2432790.147 -1254 -0.187 pg 1 Shakhovskaya (1964) 2436199.34 -828 -0.03 pg 0.5 Richter (1973) Table 48 (cont.) Obs.Max.J.D. E O-C Type w Reference 2436607.456 -777 -0038 pg 1 Shakhovskaya (1964) 2436831.503 -749 -0.059 pe 2 Oosterhoff (1960) 2437191.72 -704 +0.05 pg 0.5 Richter (1973) 2437631.762 -649 -0.044 pe 3 Mitchell et al. (1964) 2438087.99 -592 +0.05 pg 0.5 Richter (1973) 2439072.166 -469 -0.077 pe 3 Takase (1969) 2439088.37 -467 +0.12 pg 0.5 Richter (1973) 2439208.368 -452 +0.083 pe 2 Wamsteker (1972) 2440616.78 -276 +0.07 pg 0.5 Richter (1973) 2442825.471 0 +0.087 pe 3 present paper Remark: 1 Observer: Kanda
Figure 74 B, B-V and U-B curves of BK Aur
Figure 75 O-C diagram of BK Aur S Sagittae The light and colour curves of this Cepheid are plotted in Fig. 76. S Sge is a component of a binary system (Herbig and Moore 1952) with an orbital period of 676.2d.
Figure 76 B, B-V and U-B curves of S Sge The O-C residuals have been computed with the formula: C = 2442678.792 + 8.382086d*E The O-C diagram in Fig. 77 shows one change in the period: before J.D. 2418000 P = 8.381968d , after J.D. 2418000 P = 8.382086d . Unfortunately, the light-time effect caused by the orbital motion around the common centre of gravity cannot be seen in the O-C diagram. The possible causes of this imperfection are as follows: - the light-time effect itself has to be small due to the comparatively short orbital period; - the pulsation period is not short enough to reduce the uncertainty in determining the phase of the individual normal maxima; - the individual observational series sometimes covers an interval longer than one year. This makes it difficult to point out an effect which has a periodicity with a value shorter than two years.
Figure 77 O-C diagram of S Sge Table 49 O-C residuals for S Sge Obs.Max.J.D. E O-C Type w Reference 2406603.4 -4304 +1.1d vis 0 Chandler (1886) 2407633.4 -4181 +0.1 vis 0.5 Chandler (1886) 2407951.9 -4143 +0.1 vis 0.5 Chandler (1886) 2408313.1 -4100 +0.9 vis 0.5 Chandler (1886) 2408782.4 -4044 +0.8 vis 0.5 Chandler (1886) 2409050.4 -4012 +0.5 vis 0.5 Chandler (1886) 2409444.4 -3965 +0.6 vis 0.5 Chandler (1886) 2409770.925 -3926 +0.203 vis 0.5 Pickering et al. (1890) 2409829.793 -3919 +0.396 vis 1 Gore (1886) 2409888.258 -3912 +0.186 vis 1 Gore^1 (1886) 2409888.74 -3912 +0.7 vis 0.5 Chandler (1886) 2410114.4 -3885 0.0 vis 0.5 Espin (1886) 2410164.999 -3879 +0.319 vis 1 Gore (1887) 2410215.45 -3873 +0.48 vis 0.5 Sawyer (1888) 2410233.6 -3871 +1.8 vis 0 Reed (1888) 2410516.65 -3837 -0.08 vis 0.5 Sawyer (1895) 2410567.248 -3831 +0.227 vis 1 Gore (1888) 2410877.36 -3794 +0.20 vis 0.5 Sawyer (1895) 2410911.55 -3790 +0.86 vis 0 Yendell (1889, 1890a) 2410944.555 -3786 +0.341 vis 0.5 Gore (1889) 2411245.94 -3750 -0.03 vis 0.5 Sawyer (1895) 2411263.052 -3748 +0.318 vis 1 Gore (1890) 2411288.36 -3745 +0.48 vis 0.5 Yendell (1890b) 2411590.73 -3709 +1.10 vis 0, Yendell (1891) 2411615.078 -3706 +0.297 vis 1 Gore (1891) 2411975.160 -3663 -0.051 vis 1 Markwick (1892) 2411976.72 -3663 +1.51 vis 0 Yendell (1892) 2412336.76 -3620 +1.12 vis 0 Yendell (1893) 2412386.12 -3614 +0.19 vis 0.5 Sawyer (1895) Table 49 (cont.) Obs.Max.J.D. E O-C Type w Reference 2412680.70 -3579 +1.39d vis 0 Yendell (1894) 2412713.12 -3575 +0.29 vis 0.5 Sawyer (1895) 2413005.63 -3540 -0.58 vis 0 Yendell (1895) 2413039.92 -3536 +0.18 vis 0.5 Sawyer (1896) 2413786.45 -3447 +0.71 vis 0 Yendell (1897b) 2414196.461 -3398 -0.003 vis 1 Pickering (1904) 2414548.747 -3356 +0.236 vis 0.5 Luizet (1905a) 2414867.554 -3318 +0.523 vis 0.5 Luizet (1905a) 2414868.58 -3318 +1.55 vis 0 Yendell (1900) 2414934.134 -3310 +0.047 vis 1 Prittwitz (1901) 2415228.055 -3275 +0.595 vis 0.5 Luizet (1905a) 2415596.116 -3231 -0.156 vis 0.5 Tass (1925) 2415596.803 -3231 +0.531 vis 0.5 Luizet (1905a) 2415948.687 -3189 +0.367 vis 0.5 Luizet (1905a) 2416082.542 -3173 +0.109 vis 1 Tass (1925) 2416325.776 -3144 +0.262 vis 0.5 Luizet (1905a) 2416711.205 -3098 +0.115 vis 0.5 Terkán (1905) 2416728.221 -3096 +0.367 vis 0.5 Luizet (1905a) 2416761.137 -3092 -0.245 pg 0.5 Lau (1907) 2416761.439 -3092 +0.057 vis 1 Lau (1907) 2416803.375 -3087 +0.082 vis 1 Tass^2 (1925) 2417062.887 -3056 -0.250 vis 1 Wilkens (1906) 2417632.674 -2988 -0.445 pg 1 Jordan (1919) 2417850.862 -2962 -0.191 pg 1 Hertzsprung (1909) 2417851.029 -2962 -0.024 vis 1 Nijland (1923) 2417851.054 -2962 +0.001 vis 1 Zeipel (1908) 2418035.437 -2940 -0.022 vis 1 Tass^3 (1925) 2418152.813 -2926 +0.005 vis 1 Nijland (1923) 2418304.62 -2908 +0.93 vis 0 Severny^4 (1933) 2418521.561 -2882 -0.059 vis 1 Nijland (1923) 2418806.555 -2848 -0.056 vis 1 Nijland (1923) 2418915.683 -2835 +0.105 pg 0.5 Robinson (1933) 2418924.031 -2834 +0.071 vis 0.5 Jost (1913) 2418957.443 -2830 -0.046 pg 2 Hertzsprung (1917) 2419225.47 -2798 -0.24 vis 0.5 Severny4 (1933) 2419317.859 -2787 -0.059 pg 2 Hertzsprung (1917) 2419770.41 -2733 -0.14 vis 0.5 Severny^4 (1933) 2420064.066 -2698 +0.142 vis 0.5 Hoffmeister (1915) 2420198.22 -2682 +0.18 vis 0.5 Dziewulski (1930) 2420499.64 -2646 -0.15 vis 0.5 Severny^4 (1933) 2421061.385 -2579 -0.007 vis 1 Luyten (1922) 2421237.94 -2558 +0.52 vis 0 Severny^4 (1933) 2421488.867 -2528 -0.012 vis 1 Lacchini (1921a) 2421748.891 -2497 +0.168 vis 1 Luyten (1922) 2422192.987 -2444 +0.013 vis 1 Leiner (1926) 2422327.13 -2428 +0.04 vis 0.5 Severny^4 (1933) 2422897.156 -2360 +0.087 vis 1 Eaton^5 (1920,1921,1922) Walkers (1921,1922) 2423056.23 -2341 -0.10 vis 0.5 Severny^4 (1933) 2423316.013 -2310 -0.160 vis 1 Nielsen (1927) 2423333.038 -2308 +0.100 vis 1 AFOEV (1922, 1923) 2423785.27 -2254 -0.300 vis 0.5 Severny^4 (1933) 2424154.59 -2210 +0.208 vis 0.5 Severny^6 (1933) Table 49 (cont.) Obs.Max.J.D. E O-C Type w Reference 2424213.006 -2203 -0.051d vis 1 Parenago (1938a) 2424423.12 -2178 +0.51 vis 0 Dziewulski (1930) 2424690.941 -2146 +0.106 vis 1 Leiner (1938) 2424774.587 -2136 -0.069 vis 1 Kukarkin (1940) 2425134.962 -2093 -0.124 pg 1 Hellerich (1935) 2425202.19 -2085 +0.05 vis 0.5 Lause (1937) 2425386.645 -2063 +0.096 vis 1 Leiner (1938) 2425445.085 -2056 -0.138 vis 1 Zverev (1936) 2425453.702 -2055 +0.097 vis 1 Kukarkin (1940) 2425537.692 -2045 +0.266 vis 0.5 Parenago (1938a) 2425797.187 -2014 -0.084 vis 1 Zverev (1936) 2425847.689 -2008 +0.126 vis 1 Leiner (1938) 2426182.943 -1968 +0.096 vis 1 Leiner (1938) 2426384.157 -1944 +0.140 vis 1 Parenago (1938a) 2426451.214 -1936 +0.141 vis 1 Kukarkin (1940) 2426476.126 -1933 -0.094 vis 1 Zverev (1936) 2426585.34 -1920 +0.15 vis 0.5 Miczaika^7 (1937) 2426794.741 -1895 +0.002 pg 1 Kox (1935) 2426920.633 -1880 +0.163 vis 1 Florya, Kukarkina (1953) 2427591.056 -1800 +0.019 vis 1 Krebs (1935) 2427599.498 -1799 +0.079 vis 0.5 Dziewulski (1948) 2428001.975 -1751 +0.216 vis 1 Krebs (1936) 2428052.51 -1745 +0.46 vis 0 Sures (1937) 2429091.599 -1621 +0.168 vis 1 Leiner (1938) 2429141.833 -1615 +0.110 pe 3 Bennett (1939) 2430055.43 -1506 +0.06 vis 0.5 Conceicao-Silva (1948) 2433131.605 -1139 +0.009 pe 3 Eggen (1951) 2433198.520 -1131 -0.133 pg 1 Solov'yov (1959) 2434036.880 -1031 +0.019 pg 1 Solov'yov (1959) 2434598.351 -964 -0.110 pg 1 Solov'yov (1959) 2434615.241 -962 +0.016 pe 3 present paper^8 2435218.65 -890 -0.08 vis 0.5 Marks (1959) 2435285.815 -882 +0.023 pe 2 Irwin (1961) 2435403.191 -868 +0.050 pg 1 Solov'yov (1959) 2435730.121 -829 +0.078 pe 3 Prokof'yeva (1961) 2435730.154 -829 +0.111 pg 1 Solov'yov (1959) 2436048.551 -791 -0.011 pg 1 Solov'yov (1959) 2436190.964 -774 -0.093 vis 1 Latyshev (1969) 2436207.768 -772 -0.054 pe 1 Svolopoulos (1960) 2436450.962 -743 +0.060 pg 1 Solov'yov (1959) 2436459.445 -742 +0.161 pg 1 Solov'yov (1959) 2436509.621 -736 +0.044 pe 3 Walraven et al. (1958) 2436718.940 -711 -0.189 vis 1 Azarnova (1960) 2437213.656 -652 -0.016 pe 3 Mitchell et al. (1964) 2437917.700 -568 -0.067 pe 3 Walraven et al. (1964) 2439040.928 -434 -0.039 pe 3 Wisniewski et al. (1968) 2440834.696 -220 -0.037 pe 2 Evans (1976) 2442595.144 -10 +0.173 pg 1 Berdnikov (1977) 2442678.783 0 -0.009 pe 3 present paper Remarks: (observers) 1 Espin; 2 Terkán; 3 Czuczi; 4 Sharbe; 5 Mundt; 6 Vorontsov-Velyaminov; 7 Plassmann; 8 Detre GQ Orionis There is a bright NW companion near the variable. The light and colour curves of GQ Ori are plotted in Fig. 78. The value of
Figure 78 B, B-V and U-B curves of GQ Ori
Figure 79 O-C diagram of GQ Ori the period was determined by a least squares fitting procedure using all the normal maxima in Table 50, i.e. including the early uncertain point with a weight of 0.5 . The O-C residuals have been calculated using the ephemeris: C = 2442798. 358 + 8.616068d*E The O-C diagram in Fig. 79 can be approximated by a straight line. Table 50 O-C residuals for GQ Ori Obs.Max.J.D. E O-C Type w Reference 2427866.7 -1733 0.0d pg 0.5 Kukarkin et al. (1947) 2441066.557 -201 +0.029 pe 2 Pel (1976) 2441368.070 -166 -0.021 pe 3 Wachmann (1976) 2442798.348 0 -0.010 pe 3 present paper IX Cassiopeiae According to the G.C.V.S. (Kukarkin et al. 1969-1970) this Cepheid belongs to Population II. The light and colour curves of IX Cas are shown in Fig. 80 . The actual value of the period (P = 9.1582) has been determined using the latest photographic
Figure 80 B and B-V curves of IX Cas and the recent photoelectric observations (see Table 51), but this value is not sufficiently accurate for deriving the O-C residuals. For this reason the O-C residuals have been computed by the formula: C = 2442779.743 + 9.153375d*E , where the value of the period is based only on the photoelectric observations. The O-C diagram in Fig. 81 shows continuous change in the period after J.D. 2428700. Before J.D. 2419000 the epochs of the normal maxima are uncertain because of the unknown trend of the O-C curve between J.D. 2419000 and J.D. 2428000, i.e. during the gap in the observations.
Figure 81 O-C diagram of IX Cas
Table 51 O-C residuals for IX Cas
Obs.Max.J.D. E O-C Type w Reference
2414740.3 -3064 +6.5d pg 0.5 Eelsalu^1 (1956)
2416753.0 -2844 +5.5 pg 0.5 Eelsalu^1 (1956)
2417485.3 -2764 +5.5 pg 0.5 Eelsalu^1 (1956)
2418528.7 -2650 +5.4 pg 0.5 Eelsalu^1 (1956)
2428750.013 -1534 +11.547 pg 1 Florya (1949)
2429152.454 -1490 +11.240 pg 1 Florya (1949)
2429481.731 -1454 +10.995 pg 1 Florya (1949)
2429902.019 -1408 +10.228 pg 1 Eelsalu (1956)
2430677.66 -1323 +7.83 pg 0.5 Vasil'yan. et al. (1970)
2431262.38 -1259 +6.74 pg 0.5 Vasil'yan. et al. (1970)
2431701.332 -1211 +6.326 vis 0.5 Tsessevich (1952)
2432733.59 -1098 +4.25 pg 0.5 Vasil'yan. et al. (1970)
2433172.010 -1050 +3.311 pg 1 Eelsalu (1956)
2433355.055 -1030 +3.288 pg 0.5 Vasil'yan. et al. (1970)
2434323.493 -924 +1.469 pg 0.5 Eelsalu (1956)
2436757.32 -658 +0.50 pg 0.5 Vasil'yan. et al. (1970)
2436802.628 -653 +0.039 pe 3 Oosterhoff (1960)
2436838.881 -649 -0.322 pg 1 Makarenko (1969)
2436903.237 -642 -0.039 pe 3 Bahner et al. (1962)
2437195.867 -610 -0.317 pg 1 Makarenko (1969)
2437204.831 -609 -0.507 pe 1 Mitchell et al. (1964)
2437543.22 -572 -0.79 pg 0.5 Vasil'yan. et al. (1970)
2437589.059 -567 -0.720 pg 1 Makarenko (1969)
2437917.951 -531 -1.350 pg 1 Makarenko (1969)
2437974.225 -525 +0.004 pe 1 Williams (1966)
2438293.185 -490 -1.404 pg 1 Makarenko (1969)
2438403.77 -478 -0.66 pg 0.5 Vasil'yan. et al. (1970)
2438677.266 -449 -1.765 pg 1 Makarenko (1969)
2439025.048 -410 -1.811 pg 1 Makarenko (1969)
2442779.743 0 0.000 pe 3 present paper
Remark: 1 observer: Florya
FN Aquilae
The V and B amplitudes of the light variation in this Cepheid are smaller than given
by Schaltenbrand and Tammann (1971). The O-C residuals have been calculated using the
formulae:
C_{max} = 2442796.744 + 9.481603d*E ,
C_{med} = 2442794.772 + 9.481603d*E .
The O-C diagram in Fig. 83 shows a constant period in contrast with the period variation
reported by Kukarkin et al. (1974).
Figure 82 B, B-V and U-B curves of FN Aql
Figure 83 O-C diagram of FN Aql Table 52 O-C residuals for FN Aql (maximum brightness) Obs.Max.J.D. E O-C Type w Reference 2425910.058 -1781 +0.049d vis 1 Lause (1930) 2425938.250 -1778 -0.204 pg 1 Prager (1931) 2429845.079 -1366 +0.205 pg 1 Solov'yov (1946b) 2430944.810 -1250 +0.070 pg 1 Solov'yov (1946b) 2431712.692 -1169 -0.058 pg 1 Solov'yov (1946b) 2433115.978 -1021 -0.049 pe 3 Eggen (1951) 2435277.891 -793 +0.058 pe 2 Irwin (1961) 2435363.221 -784 +0.054 pe 2 Walraven et al. (1958) 2436794.727 -633 -0.162 pg 1 Makarenko (1969) 2437174.083 -593 -0.070 pg 1 Makarenko (1969) 2437211.945 -589 -0.135 pe 2 Mitchell et al. (1964) 2437354.15 -574 -0.15 pg 0.5 Jetschke (1969) 2437478.031 -561 +0.466 pg 0 Zoj Von Shor (1963) 2437505.895 -558 -0.115 pg 1 Makarenko (1969) 2437885.65 -518 +0.38 pg 0 Jetschke (1969) 2437951.901 -511 +0.256 pe 1 Williams (1966) 2437961.175 -510 +0.049 pg 1 Makarenko (1969) 2438369.20 -467 +0.37 pg 0 Jetschke (1969) 2438558.45 -447 -0.02 pg 0.5 Jetschke (1969) 2438805.113 -421 +0.124 pg 1 Makarenko (1969) 2439051.66 -395 +0.15 pg 0.5 Jetschke (1969) 2439317.24 -367 +0.24 pg 0.5 Jetschke (1969) 2439763.02 -320 +0.39 pg 0 Jetschke (1969) 2440862.589 -204 +0.092 pe 3 Pel (1976) 2442047.698 -79 +0.001 pe 3 Vasil'yanovskaya (1977) 2442796.691 0 -0.053 pe 3 present paper 2442900.967 +11 -0.075 pe 2 Dean (1977) Table 53 O-C residuals for FN Aql (median brightness) Obs.Med.J.D. E O-C Type w Reference 2430942.800 -1250 -0.032 pg 1 Solov'yov (1946b) 2433114.138 -1021 +0.083 pe 3 Eggen (1951) 2440860.711 -204 +0.186 pe 3 Pel (1976) 2442045.564 -79 -0.161 pe 3 Vasil'yanovskaya (1977) 2442794.652 0 -0.120 pe 3 present paper DD Cassiopeiae The light and colour curves of this Cepheid are shown in Fig. 84. There is a B4 photometric companion (Madore 1977). The O-C residuals have been computed using the formula: C = 2442780.493 + 9.812027d*E The O-C diagram in Fig. 85 shows one change in the period: before J.D. 2418600 P = 9.807272d , after J.D. 2418600 P = 9.812027d . The O-C diagram also shows some sinusoidal variation which is
Figure 84 B and B-V curves of DD Cas
Figure 85 O-C diagram of DD Cas
the result of the light-time effect (orbital motion of DD Cas around the common centre of
gravity of the binary system). A search for the orbital period gave the value:
P_{orb} = 8500 ą 1000 days which seems to be a reasonable value for a pair consisting of a
supergiant and an early type star. The O-C residuals used in determining the orbital period
as well as the corresponding orbital phases are listed in Table 55. The arbitrary zero point
of the phase calculation is J.D. 2400000. The plot of O-C variation vs. the orbital phase is
seen in Fig. 86 . The value of a* sin i can be determined from the amplitude of this curve:
a* sin i = 6.5*10^9 km .
Figure 86 O-C variations due to the orbital motion
Table 54 O-C residuals for DD Cas
Obs.Max.J.D. E O-C Type w Reference
2415612.45 -2769 +1.46d pg 0.5 Romano (1959)
2416711.37 -2657 +1.43 pg 0.5 Romano (1959)
2417063.699 -2621 +0.529 pg 1 Parenago (1940)
2417151.96 -2612 +0.48 pg 0.5 Romano (1959)
2418927.41 -2431 -0.04 pg 0.5 Romano (1959)
2425128.46 -1799 -0.20 vis 0.5 Stuker (1932)
2427297.39 -1578 +0.28 pg 0.5 Romano (1959)
2427779.22 -1529 +1.32 pg 0 Romano (1959)
2428062.95 -1500 +0.50 pg 0 Romano (1959)
2428583.21 -1447 +0.72 pg 0 Romano (1959)
2428601.841 -1445 -0.273 pg 1 Parenago (1940)
2428740.03 -1431 +0.55 pg 0 Romano (1959)
2429141.51 -1390 -0.26 pg 0.5 Romano (1959)
2429171.047 -1387 -0.165 pg 1 Parenago (1940)
2430584.472 -1243 +0.329 pg 1 Solov'yov (1958b)
2430976.962 -1203 +0.337 pg 1 Solov'yov (1958b)
2431555.704 -1144 +0.170 pg 0.5 Solov'yov (1958b)
2433861.097 -909 -0.263 pg 0.5 Solov'yov (1958b)
2435087.80 -784 -0.06 pg 0.5 Romano (1959)
2435421.30 -750 -0.17 pg 0.5 Romano (1959)
2435686.53 -723 +0.13 pg 0.5 Romano (1959)
2435833.58 -708 0.00 pg 0.5 Zonn, Semeniuk (1959)
2436137.833 -677 +0.080 pg 1 Makarenko (1969)
2436490.716 -641 -0.268 pg 1 Makarenko (1969)
2436805.022 -609 +0.053 pe 3 Oosterhoff (1960)
2436843.942 -605 -0.275 pg 1 Makarenko (1969)
2436932.506 -596 -0.019 pe 3 Bahner et al. (1962)
2437197.423 -569 -0.027 pg 1 Makarenko (1969)
2437579.945 -530 -0.174 pg 1 Makarenko (1969)
2437923.596 -495 +0.056 pg 1 Makarenko (1969)
2438296.512 -457 +0.115 pg 1 Makarenko (1969)
2438689.012 -417 +0.134 pg 1 Makarenko (1969)
2439022.410 -383 -0.077 pg 0.5 Makarenko (1969)
2442064.53 -73 +0.32 vis 0.5 Small (1974)
2442780.502 0 +0.009 pe 3 present paper
Table 55
Obs.Max.J.D. O-C phase Obs.Max.J.D. O-C phase
2428601.841 -0.273d .365 2436932.506 -0.019d .345
2429171.047 -0.165 .432 2437197.423 -0.027 .376
2430584.472 +0.329 .598 2437579.945 -0.174 .421
2430976.962 +0.337 .644 2437923.596 +0.056 .462
2436137.833 +0.080 .252 2438296.512 +0.115 .505
2436490.716 -0.268 .293 2438689.012 +0.134 .552
2436805.022 +0.053 .330 2442780.502 +0.009 .038
2436843.942 -0.275 .335
GENERAL REMARKS
Period changes
The investigation of period changes of Cepheids within the period interval 5 - 10
days is of great importance because a comprehensive study of their period changes has not
been made so far. The most authentic paper in this field (Parenago 1956) contains only seven
Cepheids within this period range; four of these seven are investigated in the present paper
too. The stability of the period of the remaining more than thirty Cepheids in this sample
has not, to all intents and purposes, previously been analyzed.
From among the 42 Cepheids in this sample 19 stars showed variability in their
period. Two of them ( eta Aql and delta Cep) have a parabolic O-C graph. This kind of period change
may be attributed to the evolution of the stars across the instability strip. The period
changes are sudden in most cases as was the case for the short period Cepheids too (Paper I).
The Cepheids showing "stepwise" O-C variations (i.e. rejumping period) can be
included with this group. There are two variables in this sample showing this phenomenon,
viz. CV Mon (see Fig. 9) and RS Ori (see Fig. 61). It is most interesting that both CV Mon
and RS Ori were reported to have a photometric companion (Madore 1977). Moreover, three stars
from Paper I which belong to the group of Cepheids with a rejumping period (SU Cyg, V 532
Cyg, SZ Tau) are also members of binaries according to Madore. The only Cepheid with a
rejumping period that is not included in Madore's list is DT Cyg. Lloyd Evans (1968),
however, pointed out that a change of -3 km/s in normal radial velocity occurred in DT Cyg.
Further spectroscopic observations would be highly desirable to reveal any periodic variation
in the radial velocity of DT Cyg.
The above mentioned items of evidence make it possible to conclude that any Cepheid
showing a rejumping period is a member of a binary system. If the orbital plane of a binary
system is nearly parallel to the line of sight, the binary nature can be discovered on the
basis of the periodic variation of the radial velocities. The binary motion, however, can
also cause apparent period changes due to the simple light-time effect. The numerical
treatment of this effect on period changes in RR Lyrae stars was published by Coutts (1971).
The apparent period changes in Cepheids caused by the binary motion were first
studied in Paper I (FF Aql). The present sample of Cepheids contains two known spectroscopic
binaries (AW Per and S Sge). Unfortunately, the apparent period changes in S Sge cannot be
detected, partly because the value of the orbital period is too short (less than two years).
The value of the orbital period of the system containing AW Per was not known earlier. The
periodic O-C variations made it possible to determine the orbital period: P_{orb} = 10300
days (see Figs. 45 and 46). This method is, of course, less accurate than the usual method
of determining the orbital period on the basis of radial velocity measurements. Nevertheless,
the "O-C variation method" is very useful if there are not enough spectroscopic data as is
the case for DD Cas. The binary nature of this Cepheid has not been detected
spectroscopically but it can be realized photometrically (Madore 1977). The O-C diagram
constructed on the basis of the available normal maxima shows a periodicity with
P_{orb} = 8500 days (see Figs. 85 and 86). Some long period fluctuation can also be
suspected in the O-C diagram of RX Cam (see Fig. 67), but there is no evidence as to its
binary nature.
The apparent period change in a periodic variable which is a component of a binary
system can only be detected if the inclination of the orbit differs significantly from 0 degree,
otherwise the binary nature can only be discovered photometrically (if the companion has an
early spectral type - Madore 1977). Since the Cepheids with a rejumping period are thought
to be members of binary systems, it may be that one can detect both the apparent
period changes due to the orbital motion and the stepwise period changes (rejumping period)
in the same system. A check inspection of the O-C diagram for SU Cyg (Paper I, p. 77) was
able to reveal a strict periodicity in the O-C variations after the rejump of the period.
The orbital period for SU Cyg is P_{orb} = 3250ą100 days. The normal maxima, the
corresponding O-C residuals and orbital phases (with an arbitrary zero point) are collected
in Table 56. The moments of maxima and the O-C values are taken from Table 27 in Paper I,
supplemented with several more recent data (Evans, 1976; Fernie, 1979; Szabados unpublished).
The value of a* sin i can be determined from the amplitude of the O-C variation
(see Fig. 87): a* sin i = 1.5*10^9 km. Unfortunately, SU Cyg is exceptional. In other
Cepheid-binaries we can only see either the rejumping period or the wave-like apparent
period variation, and there are a lot of Cepheids listed by Madore (1977) as binaries but
their O-C diagrams are incomplete and we are thus unable to prove the binary nature.
Figure 87 O-C variations of SU Cyg due to the orbital motion
In the light of the above mentioned results, one of the conclusions drawn in Paper I
has to be changed. In Paper I the stepwise O-C diagram was declared to be observational
evidence supporting the hypothesis on the evolution of Cepheids along the lines of constant
period. The real state of affairs is that the period of Cepheids in binary systems tends to
be constant, but a phase jump in the light variation of the Cepheid (i.e. a jump in the period
and a subsequent rejump) may sometimes occur, which is certainly caused by the influence of
the companion star.
Table 56
Obs.Max.J.D. O-C phase Obs.Max.J.D. O-C phase
2433126.659 +O.081d .193 2438994.833 +0.034d .999
2433680.364 +0.035 .363 2439014.054 +0.028 .005
2434368.640 -0.032 .575 2439344.655 -0.083 .106
2434591.666 -0.044 .644 2439740.868 +0.044 .228
2435356.949 -0.014 .879 2440482.991 -0.013 .457
2435645.305 -0.070 .968 2440825.321 +0.069 .562
2436099.119 +0.024 .108 2441778.985 +0.050 .855
2437287.383 -0.017 .473 2443378.737 +0.077 .348
2437941.117 -0.017 .674 2443382.554 +0.050 .349
The instability of the period
The quantity Delta E|Delta P|/P , first suggested by Parenago (1956) as being a
measure of the instability of the period, has also been computed as was done in Paper I
(p. 109). Here Delta E is the number of epochs during which the period remained constant.
Neither the sudden period jumps in CV Mon and RS Ori nor the apparent period changes due to
the orbital motion of the binary Cepheids have been taken into consideration in these
computations. Table 57 gives a short summary on the instability of the period for different
groups of Cepheids. The successive columns contain the following data:
1. Name of the group
2. Average value of Delta E|Delta P|/P
3. Average value of Delta E
4. Average value of the period of Cepheids on which basis the preceding parameters are
derived
5. Number of investigated Cepheids in this group
6. Abbreviation of the name of the group in Table 57
Table 57
Group \overline{Delta E|Delta P|/P} \overline{Delta E} \overline P n Abbrev.
classical Cepheids 0.12 4040 6.90 34 I
with large amplitude
classical Cepheids 0.21 3500 5.86 4 Is
with small amplitude
W Vir type variables 1.24* 2370 7.61* 3* II
The asterisks in Table 57 denote that if the data concerning
Table 58 Summary of the observations
Name Period log P Norm.Max. Norm.Med. Max.-Med./P Type
Hel.J.D.2440000+
FM Aql 6.114230 0.7863 2678.229 2677.581 0.106 I
FN Aql 9.481603 0.9769 2796.691 2794.652 0.215 I
KL Aql 6.108015 0.7859 3338.696 3337.804 0.146 I?
V 336 Aql 7.303976 0.8636 3048.212 3047.270 0.129 I
V 600 Aql 7.238748 0.8597 2904.092 2903.187 0.125 I
V 733 Aql 6.178748 0.7909 2597.232 2596.225 0.163 Is*
eta Aql 7.176735 0.8559 2794.781 2793.834 0.132 I
AO Aur 6.763006 0.8301 2815.764 2814.945 0.121 I
BK Aur 8.002432 0.9032 2825.471 2824.382 0.136 I
RX Cam 7.912024 0.8983 2766.639 2765.587 0.133 I
RS Cas 6.295983 0.7991 2773.489 2772.746 0.118 I
SW Cas 5.440950 0.7357 2989.509 2988.840 0.123 I
VV Cas 6.207059 0.7929 2836.847 2836.220 0.101 I
VW Cas 5.993859 0.7777 2778.699 2777.961 0.123 I
DD Cas 9.812027 0.9918 2780.502 2778.128 0.242 I
DL Cas 8.000669 0.9031 2780.311 2778.935 0.172 I
FM Cas 5.809284 0.7641 2817.752 2816.881 0.150 I
IX Cas 9.1582 0.9618 2779.743 2777.380 0.258 II
CR Cep 6.232964 0.7947 2774.223 2773.263 0.154 Is*
delta Cep 5.366270 0.7297 2756.458 2755.798 0.123 I
VY Cyg 7.856982 0.8953 3045.328 3044.424 0.115 I
GH Cyg 7.817930 0.8931 2743.705 2742.688 0.130 I
MW Cyg 5.954586 0.7749 2923.911 2923.078 0.140 I
V 386 Cyg 5.257606 0.7208 2777.160 2776.508 0.124 I
V 538 Cyg 6.118961 0.7867 2772.938 2771.965 0.159 I
V 924 Cyg 5.571472 0.7460 3066.098 3065.056 0.187 Is
TX Del 6.165907 0.7900 2947.033 2945.862 0.190 II
W Gem 7.913779 0.8984 2755.172 2754.293 0.111 I
RZ Gem 5.529286 0.7427 2714.927 2714.484 0.080 I
BB Her 7.507945 0.8755 2679.245 2678.104 0.152 II?
X Lac 5.444990 0.7360 2738.227 2737.296 0.171 Is*
RR Lac 6.416243 0.8073 2776.720 2775.905 0.127 I
BG Lac 5.331932 0.7269 2673.231 2672.490 0.139 I
CS Mon 6.731920 0.8281 2673.488 2672.445 0.155 I
CV Mon 5.378898 0.7307 2773.160 2772.520 0.119 I
RS Ori 7.566881 0.8789 2820.794 2819.879 0.121 I
GO Ori 8.616068 0.9353 2798.348 2797.167 0.137 I
AW Per 6.463589 0.8104 2709.062 2708.363 0.108 I
HR 690(Per) 7.552 0.878 3483.394 3481.604 0.237 Is
S Sge 8.382086 0.9234 2678.783 2677.701 0.129 I
U Vul 7.990629 0.9026 2526.328 2525.281 0.131 I
X Vul 6.319543 0.8007 2665.923 2665.101 0.130 I
* Small amplitude, but non-sinusoidal light curve
V_{max} V_{min} A_V B_{max}B_{min} A_B U_{max} U_{min} A_U Name
7.89m 8.66m 0.77m 9.05m 10.13m 1.08m 9.75m 11.15m 1.40m FM Aql
8.22 8.75 0.53 9.34 10.15 0.81 10.23: 11.26 1.03: FN
9.84 10.56 0.72 10.66 11.71 1.05 KL
9.50 10.27 0.77 10.67 11.74 1.07 V 336
9.73 10.40 0.67 11.08 12.04 0.96 V 600
9.73 10.16 0.43 10.53 11.23 0.70 V 733
3.57 4.30 0.73 4.17 5.29 1.12 4.49 6.05 1.56 eta
10.38 11.30 0.92 11.24 12.57 1.33 AO Aur
9.12 9.83 0.71 10.04 11.07 1.03 10.66 11.96 1.30 BK
7.31 8.03 0.72 8.40 9.49 1.09 9.13 10.61 1.48 RX Cam
9.56 10.36 0.80 10.83 11.95 1.12 RS Cas
9.34 9.98 0.64 10.31 11.24 0.93 SW
10.28 11.18 0.90 11.21 12.49 1.28 VV
10.36 11.05 0.69 11.43 12.39 0.96 VW
9.59 10.16 0.57 10.69 11.56 0.87 DD
8.69 9.26 0.57 9.74 10.56 0.82 10.47 11.41: 0.94: DL
8.85 9.47 0.62 9.71 10.61 0.90 FM
11.19 11.71 0.52 11.79 12.50 0.71 IX
9.45 9.81 0.36 10.79 11.35 0.56 CR Cep
3.50 4.33 0.83 3.95 5.18 1.23 4.30 5.85 1.55 delta
9.20 9.99 0.79 10.29 11.44 1.15 VY Cyg
9.50 10.33 0.80 10.61 11.68 1.07 GH
9.16 9.84 0.68 10.36 11.41 1.05 MW
9.27 9.94 0.67 10.67 11.67 1.00 V 386
10.22 10.73 0.51 11.39 12.17 0.78 V 538
10.57 10.85 0.28 11.36 11.75 0.39 V 924
8.88 9.51 0.63 9.42 10.46 1.04 9.91 11.35 1.44 TX Del
6.55 7.34 0.79 7.29 8.49 1.20 7.81 9.41 1.60 W Gem
9.49 10.46 0.97 10.38 11.67 1.29 RZ
9.80 10.43 0.63 10.69 11.63 0.94 BB Her
8.20 8.57 0.37 9.03 9.62 0.59 9.57 10.36 0.79 X Lac
8.43 9.23 0.80 9.16 10.30 1.14 9.59 11.09 1.50 RR
8.55 9.15 0.60 9.39 10.24 0.85 9.89 10.99 1.10 BG
10.71 11.28 0.57 11.80 12.53 0.73 CS Mon
9.95 10.57 0.62 11.13 11.99 0.86 CV
8.02 8.86 0.84 8.83 10.03 1.20 9.33 10.89 1.56 RS Ori
8.66 9.30 0.64 9.47 10.50 1.03 10.08 11.30 1.22 GQ
7.06 7.84 0.78 7.97 9.06 1.09 8.55 9.82 1.27 AW Per
6.19 6.30 0.11 7.04 7.17 0.13 7.66 7.80 0.14 HR 690
5.31 6.01 0.70 5.92 7.03 1.11 6.32 7.80 1.48 S Sge
6.79 7.50 0.71 7.92 8.95 1.03 8.76 10.17 1.41 U Vul
8.47 9.20 0.73 9.75 10.81 1.06 10.76 12.12 1.36 X
IX Cas are omitted from the statistics the corresponding data in the last line would be:
\overline{Delta E|DeltaP|/P = 0.19, \overline P = 6.84d. This difference shows that the
data on W Vir type variables are not to be taken seriously since the number of Population II
Cepheids in this sample is too small. The measure of the instability of the period for the
small amplitude Cepheids is somewhat smaller than for their shorter period group in Paper I.
This means that the instability of the period of the small amplitude Cepheids does not
increase with the increase in the value of the period. This evidence supports the hypothesis
that the small amplitude Cepheids must be separated from their counterparts with normal
amplitude (see Paper I, p. 108). The increasing instability with the increase in the period
can be seen in the case of the normal amplitude Cepheids when comparing the corresponding
data from the present Table 57 and Table 44 in Paper I: at an average period of 4.1d the
measure of the instability is 0.03 , and for P = 6.9d the instability is 0.12 . All these
data, however, are affected by the rather uncertain value of \overline{Delta E}. In most
cases the value of Delta E is only a lower limit and its certainly larger real value can only be
determined if more period changes are observed.
Summary of the observations
The fundamental parameters of the light variations of the observed Cepheids are
summarized in Table 58. The successive columns contain the following data:
1. Name of the Cepheid
2. Period of light variation
3. Decimal logarithm of the period
4-5. The moments of the normal maximum and normal median brightnesses derived from the
observations listed in Table 3
6. Fractional period between the moment of median brightness and that of the subsequent
light maximum (a measure of the asymmetry of the light curve)
7-9. The maximum and minimum magnitudes and the amplitude in V
10-12. The corresponding quantities for B as under 7-9
13-15. The corresponding quantities for U as under 7-9
16. Type of Cepheid
17. Name of Cepheid
Acknowledgements
I am indebted to Dr. Bela Szeidl for many valuable discussions and for his continuous
interest. I should like to thank the night assistants of the Konkoly Observatory for
participating in the observations; Mrs. E. Toth and Mr. H. Shenker are thanked for their
help in preparing the manuscript.
Budapest-Szabadsaghegy, April 20, 1980
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