Fig. 1. The identification chart of Nova Her 1963 (cross) with the comparison stars.
used for the photoelectric measures greatly exceeded their separation. All magnitudes and
colours of Nova Her 1963 relative to BD +42 3035 are listed in Table II in our
"1963 IX-XII" photometric system (see later).
Table II
J. D. Delta y Delta(b-y) Delta(u-b) J. D. Delta y Delta(b-y) Delta(u-b)
2438... 2438...
069.615 -1.386 +0,066 - 078.607 -0.813: +0.085: -0.313:
.617 -1.453 +0.136 -0.324 .611 -0.841: +0.126: -0.329:
.623 -1.444 +0.114 -0.328 .617 -0.750: +0.081: -0.336:
.637 -1.403 +0.101 -0.326 .620 -0.814: +0.092: -0.318:
.642 -1.422 +0.116 -0.330
.657 -1.402 +0.082 -0.301 082.601 -0.389 +0.085 -0.329
.662 -1.423 +0.105 -0.298 .605 -0.398 +0.111 -0.337
.665 -1.367 +0.052 -0.299 .609 -0.374 +0.110 -0.375
.668 -1.422 +0.109 -0.301 .610 -0.352 +0.077 -0.361
.675 -1.409 +0.091 -0.295 .612 -0.346 +0.066 -0.343
.677 -1.412 +0.100 -0.301
.681 -1.419 +0.098 -0.303 090.570 -0.477 +0.061 -0.271
.687 -1.417 +0.103 -0.308 .571 -0.474 +0.051 -0.268
.689 -1.337 +0.022 -0.299 .576 -0.465 +0.046 -0.282
.692 -1.415 +0.109 -0.311 .577 -0.471 +0.042 -0.269
.698 -1.395 +0.079 -0.314 .579 -0.474 +0.053 -0.296
.701 -1.417 +0.099 -0.313
.703 -1.411 +0.089 -0.307 104.579 +0.442: -0.038: -0.275:
J. D. Delta y Delta(b-y) Delta(u-b) J. D. Delta y Delta(b-y) Delta(u-b)
2438... 2438...
104.584 +0.450 -0.066 -0.299 180.405 +2.274 +0.364 -
.586 +0.426 -0.045 -0.261 .410 +2.265 +0.311 -
.591 +0.364 -0.031 -0.254 .417 - - -0.004
.592 +0.424 -0.089 -0.310 .417 - - +0.005
.421 - - +0.006
113.563 +0.610: -0.098: -0.247 .422 - - +0.017
.568 +0.638 -0.109 -0.244 .427 +2.291 +0.273 +0.032
.569 - - -0.246 .428 +2.319 +0.247 +0.028
.573 +0.609 -0.074 -0.245 .430 +2.317 +0.263 +0.016
.575 +0.645 -0.103 -0.258 .431 +2.353 +0.234 +0.003
.578 +0.618 -0.078 -0.257
.580 +0.627 -0.081 -0.266 197.486 +2.459 +0.339 +0.094
.493 +2.421 +0.396 -
114.564 +0.870 -0.134: -0.246: .495 +2.407 +0.372 +0.082
.569 +0.825 -0.099 -0.253 .509 +2.477 +0.354 +0.062
.570 +0.829 -0.110 -0.253 .511 +2.463 +0.335 +0.097
.572 +0.828 -0.114 -0.245 .519 +2.457 +0.380 +0.104
.576 +0.838 -0.119 -0.255 .521 +2.505 +0.356 +0.145
.578 +0.834 -0.111 -0.255 .523 +2.478 +0.362 +0.088
.581 +0.832 -0.099 -0.256
.583 +0.838 -0.105 -0.258 220.375 +2.698 +0.514 +0.252
.377 +2.691 +0.511 +0.276
118.549 +0.528 -0.082 -0.233
.551 +0.540 -0.077 -0.249 223.353 +2.778: +0.519: +0.272
.568 +0.527 -0.062 -0.271 .356 +2.746: +0.554: +0.229
.569 +0.534 -0.082 -0.235 .362 +2.762 +0.526 +0.291
.573 +0.533 -0.072 -0.242 .364 +2.732 +0.551 +0.287
.369 +2.751 +0.565 +0.275
126.539 +1.144 -0.175 -0.223 .371 +2.828: +0.462: +0.278
.541 +1.146 -0.170 -0.233 .373 +2.728 +0.541 +0.297
.545 +1.147 -0.167 -0.234 .379 +2.740 +0.556 +0.293
.547 +1.160 -0.173 -0.242 .381 +2.752 +0.521 +0.278
.551 +1.176 -0.197 -0.238
.553 +1.176 -0.143 -0.217 224.504 +2.710 +0.599 +0.279
.555 +1.178 -0.187 -0.235 .507 +2.716 +0.576 +0.307
.512 +2.697 +0.606 +0.280
159.515 +1.775 +0.110 -0.038 .515 +2.709 +0.577 +0.277
.516 +1.781 - - .539 +2.760 +0.576 +0.194
.522 +1.738 +0.125 -0.076 .547 +2.721 +0.548 +0.348
.524 +1.759 +0.136 -0.073 .549 +2.740 +0.633 +0.258
.527 +1.783 +0.129 -0.038
.534 +1.758 +0.109 -0.077 236.506 +2.872 +0.701 -
.536 - - -0.070 .514 +2.871 +0.694 +0.323
.544 +1.775 - - .519 +2.857 +0.683 +0.274
.549 +1.793 +0.062 -0.092 .521 +2.860 +0.697 +0.380
.553 +1.779 +0.063 -0.059 .526 +2.855 +0.709 -
.555 +1.756 +0.059 -0.072 .528 - - +0.226
.562 +1.773 +0.213 -0.186 .530 +2.870 +0.673 -
.565 +1.772 +0.084 -0.066 .531 - - +0.301
.567 +1.770 +0.079 -0.060
241.519 +2.925 +0.673 +0.391:
160.444 +1.849 +0.088 -0.078 .521 +2.953 +0,607 +0.437:
.446 +1.841 +0.074 -0.046 .547 +2.904 +0.664 +0.446:
.452 +1.832 +0.081 -0.026 .549 +2.946 +0.654 +0.542:
.454 +1.847 +0.074 -0.049
253.477 +3.022 +0.727 +0.490
180.404 +2.358 +0.268 - .481 +3.004 +0.841 +0.385
J. D. Delta y Delta(b-y) Delta(u-b) J. D. Delta y Delta(b-y) Delta(u-b)
2438... 2438...
253.508 +3.044: +0.591: +0.339: 439.639 +4.656 +1.512: +0.442:
.511 +3.020: +0.641: +0.292: .662 +4.639 +1.467: +0.368:
.519 +3.016 +0.612 +0.344 .670 +4.604 +1.492 +0.387
.526 +3.045: +0.608: +0.285: .675 +4.629 +1.529 +0.318
.681 +4.668 +1.458: +0.275:
261.508 +3.107 +0.898: +0.358:
.515 +3.064 +0.930 +0.374 473.599 +4.970 +1.566 +0.130
.520 +3.102: +0.919: +0.379 .604 +4.961 +1.587 +0.261
.525 +3.110 +0.915: +0,403: .609 +4.959 +1.553 +0.173
285.415 +3.369 +1.023: +0.379: 492.542 +5.047 +1.480: +0.270:
.430 +3.388 +1.047: +0.463: .549 +5.199 +1.485 +0.178
.555 +5.031 +1.257 +0.352
292.413 +3.464: +1.083: +0.359: .561 +5.137 +1.508 +0.293
.417 +3.416 +1.110 +0.416 .565 +5.073 +1.482 +0.221
.422 +3.404 +1.116 +0.421 .571 +5.094 +1.382 +0.351
.427 +3.419 +1.097: +0.388:
497.503 +5.200 +1.317 -
305.398 +3.478 +1.107 +0.457 .506 +5.081 +1.411 -
.403 +3.568 - - .509 +5.063 +1.414 -
.409 - - +0.613:
.416 +3.481 +1.139 +0.419 .512 +5.156 +1.346 -
.524 +5.166 +1.347 -
322.343 +3.710 +1.226 +0.436 .527 +5.153 +1.468 -
.528 +5.168 +1.336 -
.348 +3.725 +1.214 +0.453 .535 +5.149 +1.473 -
.354 +3.708 +1.231 +0.548 .538 +5.201 +1.333 -
.359 +3.701 +1.180 +0.473 .541 +5.187 +1.288 -
338.297 +3.810 +1.350 +0.409 .547 +5.088 +1.417 -
.302 +3.802 +1.372 +0.353 .550 +5.152 +1.352 -
.306 +3.860 +1.325 +0.329 .553 +5.138 +1.446 -
.312 +3.847 +1.326 +0.398 .562 +5.177 +1.451 -
.546 +5.116 +1.424 -
.317 +3.868 +1.204 +0.452 .568 +5.206 +1.397 -
345.278 +3.862 +1.383 +0.394 .578 +5.222 +1.380 -
.285 +3.901 +1.387 +0.242 .580 +5.239 +1.332 -
.291 - - +0.485 .588 - - +0.271
.297 +3.891 +1.319 +0.467 .589 +5.142 +1.322 -
.302 +3.876 +1.276 +0.571 .593 +5.162 +1.381 -
.595 +5.172 +1.288 -
352.290 +3.965 +1.365 +0.388: .604 +5.154 +1.377 -
.297 +3.950 +1.338 +0.438 .607 +5.135 +1.450 -
.303 +3.993 +1.359 +0.404 .610 +5.194 +1.417 -
.311 +3.946 +1.396 +0.339
371.199 +4.114 +1.432: +0.303: 522.429 - - 0.064
.205 +4.121 +1.385 +0.356 .432 +5.311 +1.441 -
.208 +4.104 +1.425 +0.384 .436 +5.321 +1.419
+0.068
.213 +4.117 +1.412 +0.356 .438 +5.292 +1.463
+0.223
.217 +4.049: +1.502: +0.380 .443 +5.305 +1.394
+0.263
.222 +4.170: +1.372: +0.320: .535 +5.286 +1.468
+0.193
.539 +5.347 +1.384 -
387.185 +4.223 +1.476: +0.407: .540 +5.384 +1.374
.192 +4.219 +1.441 +0.262 .545 - -
+0.135
.197 +4.223 +1.397 +0.406 .550 +5.391 +1.400 -
.204 +4.201 +1.502 +0.380 .551 +5.362 +1.323 -
.209 +4.249 +1.409 +0.351 .565 +5.335 +1.468 -
.214 +4.250 +1.433: +0.358: .566 +5.371 - -
.539 +5.347 +1.384 -
J. D. Delta y Delta(b-y) Delta(u-b) J. D. Delta y Delta(b-y) Delta(u-b)
2438... 2438...
524.495 +5.349 +1.328 +0.294 586.403 +5.790 +1.235 +0.085
.498 +5.353 +1.371 +0.196 .407 +5.786 +1.189 +0.058
.555 +5.365 +1.269 +0.432 .409 +5.769 +1.270 +0.068
.560 +5.477 +1.919 +0.336 .411 +5.782 +1.289 -
.563 +5.429 +1.345 +0.269 .415 +5.837 +1.248 +0.007
.420 +5.795 +1.260 +0.137
528.473 +5.398 +1.253 +0.225 .422 +0.222
.480 +5.451 +1.400: +0.109: .424 +5.808 +1.194 +0.076
.492 +5.359 +1.356 +0.136 .427 +5.804 +1.178 +0.131:
.502 +5.354 +1.370 +0.155 .430 +5.817 +1.144 +0.044:
.511 +5.393 +1.411 +0.040: .433 +5.803 +1.249: +0.062
.514 +5.398 +1.348 +0.179
.520 +5.412 +1.343 +0.168 607.379 +5.835 +1.162 +0.042
.526 +5.368 +1.366 +0.198 .388 +5.855 +1.137 -0.018:
.530 +5.401 +1.420 +0.054 .393 +5.917 +1.172 +0.254
.538 +5.381 +1.412 +0.113 .396 +5.916 +1.348 -0.040
.545 +5.388 +1.396 +0.168 .404 +5.924 +1.130 +0.078
.407 +5.867 +1.185 +0.046
529.477 +5.418 +1.350 +0.422 .415 +5.821 +1.169 +0.240
.484 +5.415 +1.381 +0.160 .419 +5.843 +1.228 +0.047
.490 +5.403 +1.330 +0.152 .427 +5.942 +1.147: +0.105:
.497 +5.425 +1.318 +0.176
.500 +5.432 +1.360 +0.141 615.334 +6.048 +1.185 +0.143
.339 +6.040 +1.231 -0.004
549.436 +5.613: +1.251: +0.131: .347 +5.971 +1.351 -0.031
.352 +6.056 +1.224 +0.098
583.378 +5.947: +1.209: +0.003 .396 +5.976 +1.296 +0.114
.385 +5.790 +1.459 +0.302 .401 +6.070 +1.260 +0.059
.391 +5.892 +1.477 +0.029 .407 +6.018 +1.322 +0.042
.399 +5.852 +1.394 0.000 .412 +5.986 +1.352 +0.241
.407 +5.866 +1.261 +0.212 .443 +6.103 +1.318 +0.114
.416 +5.903: +1.233: +0.120: .449 +6.104 +1.182 -
.453 +5.998 +1.303 -
586.365 - - +0.038 .483 +5.993 +1.084 -
.372 +5.772 +1.246 +0.066 .488 +5.949 +1.277 -
.375 +5.769 +1.155 +0.157 .505 +5.993 +1.055 -
.378 +5.795 +1.147 - .510 +6.063 +1.030: -
.382 +5.728 +1.181 +0.130
.384 +5.727 +1.284 +0.177 671.298 +6.276 +1.937: +0.195:
.389 +5.792 +1.253 +0.192 .306 +6.210 +1.098 +0.037
.391 +5.805 +1.183 - .313 +6.269 +1.088 +0.012
.393 - - +0.208 .323 +6.174 +1.078 +0.075
.395 +5.780 +1.271 +0.162 .332 +6.286 +1.150 -0.076
.399 +5.784 +1.228 +0.148 .341 +6.260 +1.076 -0.053
REDUCTION
The reduction of a long series of medium-band width photoelectric observations of
a nova to a homogeneous photometric system is hampered by the fact, that the necessary
changes over to fainter and fainter comparison stars may be accompanied by gradual changes
in the photometric system. Nevertheless it is unadvisable to rely on a single comparison
star for a large interval of magnitudes because this would reduce the accuracy of the
measurements.
Average values of the principial coefficients (k' and k'_c) and second-order
coefficients (k"_c) of the atmospheric extinction were determined separately for each
observing season using all material available at the observatory. Observed magnitudes and
colour-indices were corrected for atmospheric extinction (differential extinction included)
according to the relations [1]:
The resulting extra-atmospheric quantities are not directly comparable because of the lack
in uniformity of the whole photometric system. As a constant reference source of light was
not available, the transformation coefficients epsilon, mu, psi had to be derived by
means of several Johnson standard stars. Colours and/or magnitudes of 2-6 suitably chosen
standard stars were measured on 9 nights, together with the determination of UBV magnitudes
of the comparison stars (see Table I). Average transformation coefficients are given in
Table III as a function of time.
Table III
1963 1964
II-IV V-VIII IX-XII I-VI VII-XII
epsilon -0.15 -0.15 -0.15 -0.15 -0.15
mu 0.86 1.02 1.02 1.00 1.00
psi 0.84 1.08 1.00 0.95 0.91
We decided to reduce all observations to the photometric system of our telescope from Sept.
to Dec. 1963 as standard. Data reduced to this photometric system are marked with u, b, y.
The transformation to the UBV system which involves a considerable shift in the effective
wave-length, is inadmissible in peculiar stars like novae, where spectral deviations from
blackbody characteristics are so pronounced. We hoped that a natural system of our own
would be more realistic in this particular case. Magnitudes and colours transformed to the
"1963 IX-XII" system are given by
where the coefficients come from Table III.
Finally however a unified magnitude and colour sequence of the 5 comparison stars
in the new photometric system was needed. It was obtained by making two kinds of observations:
1. special connections to Johnson standard stars on 8 nights as mentioned above, 2. simultaneous
observations of comparison stars (sometimes alternately with the nova itself) on 30 nights.
Both kinds of results were reduced to the "1963 IX -XII" system using the known epsilon,
mu, psi values. Suitable sequences of magnitudes and colours of the 5 comparison stars
were established by trial and error. Table IV gives the result in respect to BD + 42 3035
which was the comparison star used almost exclusively by all observers of Nova Her 1963.
Table IV
y b - y u - b
B - A +2.989 +0.494 +0.508
C - A +3.369 +0.987 +1.125
D - A +5.119 +1.095 +1.225
F - A +5.452 +0.480 +0.604
Table II contains heliocentric Julian Dates of the observations and all y, b - y
and u - b values relative to BD + 42 3035. Observations in respect to other comparison
stars were transformed according to Table IV; double (simultaneous) measurements, after
being reduced to BD +42 3035, are simply averaged. Uncertain values are denoted by a colon.
Table V contains for every separate night, mean values of Delta y, Delta(b - y) and
Delta(u - b); they are plotted in figures 2 and 3.
Standard deviations on a night of moderate quality in 1963 are 0,025m in yellow,
0,006m in blue, 0.018m in ultraviolet and in 1964 0.026m in yellow, 0.048m in blue and
0.068m in ultraviolet. The lack of observations in April 1963 is due to the lengthy delay
of the new coating of the mirror.
Fig. 2. Magnitude differences between Nova Her 1963 and BD +42 3035 in yellow according to
Table V, obtained at the Konkoly Observatory. Uncertain observations are denoted by points.
Fig. 3. Colour-index curves according to Table V, obtained at the Konkoly Observatory.
Uncertain observations are denoted by points.
Table V.
J. D. Delta Delta(b-y) Delta(u-b)
2438...
069.667 -1.409 +0.093 -0.309
078.614 -0.804: +0.096: -0.324
082.607 -0.372 +0.090 -0.349
090.575 -0.472 +0,051 -0.277
104.586 +0.419: -0.055: -0.280
113.573 +0.625 -0.090 -0,252
114.574 +0.837 -0.110 -0.253
118.562 +0.532 -0.075 -0,246
126.546 +1.161 -0,173 -0.232
159.543 +1.770 +0.106 -0.076
160.449 +1.842 +0.079 -0,050
180.421 +2.311: +0.280: +0.013:
197.508 +2.458: +0.362: +0.097:
220.376 +2.695: +0.512: +0.264:
223.368 +2.753 +0.537 +0.278
224.525 +2.722 +0.588 +0.281
236.521 +2.864 +0.693 +0.301:
241.534 +2.932: +0.649: +0.454:
253.504 +3.021 +0.689: +0,373:
261.517 +3.096 +0.918 +0.378
285.423 +3.379: +1.035: +1.421:
292.420 +3.425 +1.105 +0.404
305.407 +3.509: +1.123: +0.473:
322.351 +3.711 +1.213 +0.478
338.307 +3.837 +1.315 +0.388:
345.291 +3.882: +1.345: +0,432:
352.300 +3.963 +1.365 +0.393
371.211 +4.113 +1.417 +0.358
387.200 +4.228 +1.441 +0.356
439.665 +4.639 +1.497 +0.356
473.604 +4.963: +1.569: +0.188:
492.557 +5.097: +1.428: +0.278:
497.556 +5.159 +1.382 +0.271:
522.475 - - +0.158
.506 +5.337 +1.413 -
524.534 +5.395: +1.306: +0.305
528.512 +5.391 +1.369 +0.132
529.490 +5.419 +1.348 +0.210
549.436 +5.613: +1.251: +0.131:
583.396 +5.865 +1.362 +0.141
586.402 +5.786 +1.220 +0.134
607.403 +5.880: +1.189: +0.089
615.380 - - +0.086
.421 +6.025 +1.238 -
671.319 +6.246: +1.174: -0.012
DISCUSSION
a) Beside the numerous visual and photographic observations [2, 3, 4, 5, 6, 7, 8, 9]
a lot of excellent photoelectric measurements of Nova Her 1963 has been published by
several observers up to the present time [10, 11, 12, 13, 14, 15]. Though their photometric
system may be entirely different, it is tempting to try a comparison of the light curves
obtained. The greatest number of observations of the nova was accomplished in the first 3
months after its maximum:
Peking [14] 1963 Febr. 17 - Nov. 19
Tokyo [13] 1963 Febr. 9 - Apr. 21
Leiden [12] 1963 Febr. 22 - Oct. 18
Asiago [10] 1963 Febr. 10 - May 25
Vilnius [11] 1963 Febr. 12 - March 22
(Budapest 1963 Febr. 9 - 1964 Oct. 2
In the first two cases measurements are directly expressed relative to BD +42 3035.
Nevertheless UBV magnitudes and colours of this near-by star are given by all the observers:
V B-V U-B
Peking 5.57 -0.15 -0.42
Tokyo 5.54 -0.12 -0.53
Leiden 5.602 -0.065 -0.447
Asiago 5.60 -0.19 -0.39
Vilnius 5.62 -0.14 -0.39
(Budapest 5.55 -0.13 -0.49)
In the other three cases it was easy to reduce UBV values of the nova to u, b, y varying
the magnitudes of BD +42 3035 and a reasonable coincidence could be obtained. Figure 4
gives the composite light curves compiled from measurements made in different photometric
systems in the first 66 days after the nova's maximum. The complicated and irregular light
variation of the nova (frequently averaged out in visual or photographic light curves) can
be traced from the very beginning. The remarkable coincidence of the observations seems to
be the consequence of the relatively flat intensity distribution in the spectrum of the
nova on these days, whereby the intensity measurements are insensitive to changes in the
effective wave length.
Fig. 4. All magnitude differences between Nova Her 1963 and BD +42 3035 in ultraviolet,
blue and yellow, obtained at different observatories before Apr. 4 1963.
It is worth while noting that these very pronounced light fluctuations, with a
pseudo-period of from 1.5 to 3 days, apparently did not have an effect on the
colour-indices (see Fig. 3). At the beginning of April there was a break on the b - y
colour curve and about May 10 the character of the light curves in all the three colours
changed, i.e. light fluctuations came to a sudden end.
Fig. 5. Magnitude differences between Nova Her 1963 and BD +42 3035 obtained at the
Budapest and Peking observatories. The solid lines were plotted following Fig. 4.
From that point on there is no coincidence between our light curves and those published in
the literature; the role of the effective wave length in the photometry of the nova became
decisive. One exception is to be emphasized. The filters used at the Peking Astronomical
Observatory being identical with ours, our findings also agree in the later part of the
corresponding light curves (Fig. 5). This experience shows that medium-band width photoelectric
observations of even such peculiar stars as novae are comparable in certain cases. The absence
of fluctuations on this second part of the light curves has been stated also by Breckinridge [15].
In the third part of the light curves other photoelectric observations are missing
for comparison. In order to study possible fluctuations longer series of observations were
carried out in 1964. During several nights quick, irregular variations were found. The
curves reproduced in Fig. 6 are typical examples. In the diagrams magnitudes and colours
in respect to both comparison stars are plotted separately, showing the variation in the
mutual relative y, b-y, u-b values of the comparison stars too. The existence of quick
brightness and colour fluctuations seems to be established. More confidence was given to
the reality of this phenomenon from the fact that one year later rapid changes in different
colours were observed also at the Lick Observatory from where we have received the
following private communication from Dr. G. Chincarini: "During the night June 29/30 1965
the nova was observed with the 24" reflector of the Lick Observatory in order to get
measurements in the u, b, v colours. On this night the integrator with 10 see integration
time was used. Since the signal was not as constant as for normal stars the NOVa was kept
on the diaphragm for about 1h. Changes in a and b magnitudes were observed. Because of the
good quality of the sky and the constancy of the equipment (checked as usual with a radium
source) we accepted it as a fact. The next night, I had the telescope, was on July 7/8 1965.
The star was then observed for 90 min. almost only in the u colour and the telescope was
checked by the radium source every 8 min. A direct current amplifier was used. The night
was photoelectrically good and the sky was measured every 15 min. The brightness of the sky
was however very low. In figure 7 the u and b magnitudes are given in an arbitrary scale.
The nova seems to show rapid casual fluctuations. However the observations are not enough
to see if any periodicity is present."
One of us had the opportunity to continue the photoelectric observations of Nova
Her 1963 with a photometer attached to the 122 em reflector of the Asiago Astrophysical
Observatory (Italy). The light curves (without a filter) on 16 and 28 March 1966 indicate
in addition to short-period fluctuations the presence of a minimum of approximately 40 min.
duration and 0.1 mag. depth, similar to partial eclipses of Algol type binaries.
(Observations: Table VI, composite light curve: Fig. 8.) The periodicity of the phenomenon
has not been ascertained [31].
Dr. G. Chincarini and S. Howard announce [32], however, that according to new
observations carried out at Lick Observatory on the nights April 20, 21, 22 and 27 1966 the
light curve of the nova is characterized by a) fluctuations of amplitude between 0.2 and
0.1 magnitudes and lasting from 5 to 50 minutes, b) overimposed a few minima with amplitude
of 0.1 - 0.2 magnitudes and lasting only 15 minutes.
More observations are urgently needed in order to understand the nature of the
fluctuations.
Fig. 6. Examples of rapid fluctuations in brightness and colour of the nova in 1964.
Relative light and colour curves of the near-by comparison stars are published as control
observations.
Fig. 7. Dr. Chincarini's observations at the Lick Observatory in blue and ultraviolet,
in 1965.
Fig. 8. The light curve of Nova Her 1963 composed from observations on 16 and 28 March 1966
carried out at the Asiago observatory. (16 March: crosses, 28 March: points)
Table VI
J. D. Delta m J. D. Delta m
2439 ... 2439 ...
200.6134 -0.699 .5723 -0.680:
.6176 -0.698 .5793 -0.742:
.6235 -0.709 .5827 -0.708
.6276 -0.669 .5938 -0.653
.6311 -0.670 .5949 -0.648
.6346 -0.648 .5956 -0.678
.6389 -0.627: .5966 -0.691
212.5365 -0.665 .5973 -0.677
.5369 -0.690 .6018 -0.662
.5376 -0.724 .6025 -0.647
.5407 -0.684 .6032 -0.630
.5420 -0.710 .6043 -0.608
.5448 -0.714 .6070 -0.615
.5458 -0.741 .6078 -0.616
.5490 -0.663 .6088 -0.597
.5501 -0.676 .6098 -0.599
.5529 -0.722 .6140 -0.634
.5539 -0.713 .6157 -0.657:
.5545 -0.702 .6171 -0.672:
.5556 -0.689 .6182 -0.667:
.5580 -0.676 .6230 -0.676
.5591 -0.711 .6348 -0.704
.5598 -0.709 .6373 -0.683
.5605 -0.726 .6407 -0.709
.5661 -0.675 .6432 -0.666
.5671 -0.711 .6466 -0.678
.5678 -0.715 .6515 -0.645:
.5688 -0.686
b) There is a wellknown method of Vorontsov-Velyaminov [16] to distinguish between
different parts of the light curve of a nova, plotting magnitudes against log (t-t_0). He
stated that the light curve of all but very slow novae can be transformed into straight
lines using the logarithm of the number of days which have elapsed since maximum (t-t_0) on
the axis of abscissas. It means that light curves of novae are composed from sections, all
satisfying the same exponential equation.
with different m_i and b_i values. Though the maximum of Nova Her 1963 was not observed,
several authors agree in its datum as January 27, 1963. Transforming the light curves by
Vorontsov-Velyaminov's method we obtained points on a curved, instead of a straight line
for the first part of each of the light curves. In order to express the equation of each
part of the light curves in the form given above, we tried to determine an optimum set of
parameters (t_0, b, m_0) from three points selected arbitrarily on the first part of each
of the light curves
From that point on, where the observed curve bent from the calculated one, we repeated the
procedure and similarly deduced a new set of parameters. Resulting to values are somewhat
surprising:
t_0 (J.D.24380...)
part 1 part 2 part 3
y 36 01 95
b 26 26 26
u 26 26 26
After we have found that t_0 = 2438026 gave an entirely satisfactory solution in ill three
colours, we used it as a common zero point, in spite of the fact, that it was definitely
earlier than any possible moment for the maximum. It is essential only that its use permits
us to transform the light curves into a series of straight lines, not only in the case of
the Budapest observations, but for all other photoelectric material. As has been stated
already, light curves of different authors coincide in the first part, and that of
Hungarian and Chinese observations in the second part of all light curves. This suggestion
manifests itself clearly in Fig. 9 where observed Delta u, Delta b, Delta y values are
plotted against log (t-2438026). In the second part of the diagram, after the first break,
there is a definite divergency between the corresponding sections of the logarithmic light
curves of different authors, at least, in one colour. For the sake
Fig 9. Magnitnde differences between Nova Her 1963 and BD +42 3035 versus logarithm
of time interval t-t_0, where t_0 = 2438026.
of clarity after 20 Apr. 1963 all observations of Vilnius, Tokyo, Leiden and Asiago were
omitted. The slope of all straight lines (b_1, b_2....), however, are given in Table VII.
Dates of changes in the slope of the broken lines in Fig. 9 are listed in
Table VIII.
Table VII
y b u
b_1 b_2 b_3 b_4 b_1 b_2 b_3 b_4 b_1 b_2 b_3 b_4
Budapest 6.64 4.11 6.06 8.86 6.56 8.14 9.06 6.76 6.41 10.24 6.75 4.52
Peking 6.64 4.11 6.06 - 6.56 8.14 - - 6.41 9.43 - -
Tokyo 6.64 - - - 6.56 - - - 6.41 - - -
Asiago 6.64 9.57 - - 6.56 - - - 6.41 10.44 - -
Leiden - 6.76 - - 7.10 8.70 - - - 9.36 - -
Table VIII
log (t-t_0) t
u 2.037 2438135
2.475 325
2.660 483
b 2.105 2438153
2.305 228
2.580 406
y 2.193 2438182
2.371 261
2.587 413
It is worth while noting that three observational materials (Budapest, Leiden, Peking)
afford the opportunity of determining independently the time of the first break (t_c) and
the subsequent changes in the rate of decline. The same method applied to photographic
observations by Busch [5] and Hang-Heng-rong etc. [9] yielded somewhat different results.
The "combined logarithmic light curves" also give proof of the statement in [14]
that t_c values increase with effective wave length. Later there is no such simple relation.
From logarithmic light curves it is easy to deduce the brightness and colour of the
nova at its maximum by simple extrapolation. Supposing that the maximum occured on January
27 and using our UBV = u b y values for BD +42 3035 we obtain
y_max = +3.18
(b-y)_max = -0.04
(u-b)_max = -0.79
or from the colour curves on Fig. 4
(b-y)_max = -0.07
(u-b)_max = -0.82
that is to say in the three colours respectively
y_max = 3.18
b_max = 3.11
u_max = 2.29
According to Schmidt [17] the distance and the absolute magnitude of novae can be derived
by means of the time needed for the first drop of 3 magnitudes in visual brightness
(t_3y). Thus
M_pg = -11.5 + 2.5 log t_(3y) = -7.13
yielding 1100 pc as a distance of Nova Her 1963. It is in the order of magnitude given by
Genderen [12] and Chincarini [10].
There are, however, several thorough spectroscopic observations and investigations
on Nova Her 1963 [18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29]. If we compare the
evolution of the spectrum with that of the brightness in different colours the coincidence
around April - May 1963 is apparent. The end of the "early decline" period at about 1
April, marked by the disappearance of absorption lines, by changes in the continuum and by
sudden variation in the radial velocity derived from Orion type lines [18] is accompanied
by the largest sudden decrease in brightness and by the prominent break in the b-y curve.
During the short transition stage the rate of decline changes in all colours, one after
the other. The beginning of the nebular stage (about May 1), transforming the appearance of
the whole spectrum, is marked on the light curves by the vanishing of fluctuations. The
continuous evolution of the spectrum in the nebular stage is parallelled by the relative
stability of the form of the light and colour-index curves. It would be undoubtedly
interesting to compare in details spectral and photometric variations of novae during later
stages of their evolution.
We should like to express our indebtedness to Prof. L. Rosino, Director of the
Asiago Astrophysical Observatory, for having allowed us to use their photoelectric
equipment; it is a pleasure to thank Dr. G. Chincarini for unpublished data and helping in
the observations at Asiago; finally the help of Mr's L. Fodor, K. Gefferth, A. Gesztesi and
K. Thaly in the observations and the reduction are gratefully acknowledged.
Budapest, July 1966
REFERENCES
1. R. H. Hardie: Photoelectric Reductions, in Astronomical Techniques (University of Chicago Press 1962) 2. E. Dahlgren: BAV Rundbrief 12, 3, 1963. 3. W. Quester: BAV Rundbrief 12, 3, 1963. 4. R. Weber: Bul. de la Station Astrophotographique de Mainteine 2, 5. 1, 1, 1964. 5. H. Busch: MVS 2, 4, 1964. 6. D. B. Mc Laughlin: Sky and Tel. 25, 4, 1963. 7. P. Ahnert: MVS 2, 3, 1964. 8. K. Löchel: MVS 2, 1, 1963. 9. Hang-Heng-rong and Yao Bao-an: Acta Astr. Sinica 12, 1, 1964. 10. G. Chincarini: Coelum 31, 5-6-7-10, 1963. Publ. ASP 76, 289, 1964. 11. K. Zdanavicsjus and P. Kalitis: Vilnius Biuletenis No. 10, 1964. 12. A. M. van Genderen: BAN 17, 4, 1964. 13. M. Huruhata: Tokyo Astr. Bull. 164, 1964. 14. Shen Liang-zhao etc.: Acta Astr. Sinica 12, 2, 1964. 15. J. B. Breckinridge: Publ. ASP 76, 449, 1964. 16. B. A. Woronzow - Weljaminow: Gasnebel und Neue Sterne (Verlag Kultur und Fortsehritt) 286 1953. 17. Th. Schmidt: Zs. f. Ap. 41, 182, 1957. 18. A. H. Batten: J. RAS Canada 58, 6, 1964. 19. A J. 68, 8, 1963. 20. W. C. Seitter: Bonn Weröff. 67, 1963, 21. C. B. Stephenson and K. B. Herr: Publ. ASP 75, 444, 1963. 22. N. L. Ivanova, M. A. Kazarjan and P. H. Oganesjan: A. C. 239, 1963. 23. M. Bloch and D. Chalonge: Ann. d'Astrophys. 27, 4, 1964. 24. D. Chalonge, M. Bloch, L. Divan and A. M. Fringant: Publ. Obs. Haute Provence 7, 27, 1964. 25. Y. Andrillat: Ann. d'Astrophys. 27, 5, 1964. 26. L. F. Ahlmark and K. A. Clement: Ark. Astr. 3, 26, 1964. 27. G. Chincarini: Mem. SA It. 35, 2, 1964. 28. G. Chincarini and L. Rosino: Ann. d'Astrophys. 27, 5, 1964. 29. K. Glebocki, J. Smolinski and A. Woszczyk: AA 14, 4, 1964. 30. G. Chincarini: Private communication. 31. L. Rosino: IAU Circular No. 1953 1966. 32. G. Chincarini and S. Howard: IBVS No. 139, 1966. (IBVS No. 139)
ERRATA
In Mitteilunlgen der Sternwarte der Ungarischen Akademie der
Wissenschaften Nr. 59
p. 9 last two equations read
