COMMISSION 27 OF THE I. A. U INFORMATION BULLETIN ON VARIABLE STARS Number 2059 Konkoly Observatory Budapest 1981 December 17 HU ISSN 0374-0676 PU VULPECULAE (OBJECT HONDA - KUWANO 1979) - 78.1 DAYS PERIOD Two outbursts of PU Vul were observed in 1979 and 1981. Photometric history of the object is being published by Chochol and Grygar (1982) and Belyakina et al. (1982). Duration of the flat maximum of brightness was 340 days during the first outburst. The average V magnitude of PU Vul was 8.9m at that time. [FIGURE 1] Table I Data for PU Vul and comparison stars --------------------------------------------------------------------------------------------------- Star Catalogue R.A.1950 DEC.1950 V B-V U-B Spectrum number --------------------------------------------------------------------------------------------------- Comparison 1 HD 194 011 20h20m22.3s 21d38' 43.7" 8.31 1.26 1.14 K 0 Comparison 2 HD 193 859 20h19m38.1s 21d14' 33.0" 8.22 -0.04 -0.46 A 0 Check 1 HD 193 706 20h18m48.8s 21d21' 29.2" 7.84 1.64 1.98 K 5 Check 2 BD 21d4165 20h18m37.9s 21d23' 42.6" 9.23 0.57 -0.01 PU Vul 20h19m01.1s 21d24' 43.1" 8.9* 0.55* 0.40* --------------------------------------------------------------------------------------------------- * average values during the maximum brightness in 1979 Table II U,B,V, observations of PU Vul -------------------------------------------------------------------------- HJD Phase V n B n U n Observatory 2440000+ -------------------------------------------------------------------------- 4008.55 0.834 8.947 5 9.463 5 9.818 5 SP 4009.53 0.847 8.969 5 9.461 5 9.825 10 SP 4010.41 0.858 8.935 5 9.490 5 SP 4014.52 0.911 8.975 12 9.48 17 9.355 17 B 4016.48 0.936 8.99 24 9.485 15 9.87 4 B 4023.53 0.026 9.012 5 9.526 5 9.954 5 SP 4023.55 0.026 9.01 10 9.52 6 9.94 3 B 4024.51 0.038 8.975 16 9.49 19 9.89 8 B 4025.50 0.051 8.985 28 9.51 22 9.87 17 B 4027.56 0.077 8.985 13 9.50 10 9.905 11 B 4029.49 0.102 8.970 5 9.505 5 9.956 5 SP 4088.46 0.857 8.942 1 9.472 1 SP 4116.37 0.214 8.890 15 9.460 15 9.957 15 SP 4117.39 0.227 8.891 19 9.462 19 9.953 19 SP 4146.32 0.598 8.901 5 9.539 5 10.040 6 SP 4149.36 0.637 8.918 29 9.540 29 10.072 30 SP 4154.28 0.700 8.925 3 9.55 4 10.10 4 B 4156.32 0.726 8.885 5 9.55 2 10.07 3 B 4157.31 0.738 8.89 3 9.55 5 10.075 4 B 4158.31 0.751 8.905 3 9.60 3 10.10 3 B 4159.29 0.764 8.944 22 9.627 22 10.20 22 SP 4161.32 0.790 8.925 9 9.64 4 10.18 5 B 4161.38 0.790 8.962 10 9.648 10 10.274 10 SP 4162.34 0.803 8.91 4 9.62 3 10.13 3 B 4169.34 0.892 8.95 5 9.62 6 10.13 6 B 4170.38 0.906 8.925 2 9.62 3 10.14 2 B 4173.38 0.944 9.03 2 9.66 3 10.12 2 B 4185.31 0.097 8.90 8 9.59 5 10.14 3 B 4210.24 0.416 8.78 4 B ------------------------------------------------------------ We observed PU Vul photoelectrically with 0.6 m telescopes of Skalnate Pleso (SP) and Brno (B) observatories in the year 1979. The data for comparison stars and PU Vul are in Table I. Magnitudes and colours were determined by us. Our U,B,V, observations of PU Vul are in Table II. Every value represents the average from observations made in one night. A letter n designates number of individual observations included. In view of the fact that variations in brightness with amplitude 0.26m in V were found, we tried to find the period of variations. We have included photometric observations during the flat maximum in the year 1979 made by Mahra et al. (1979), Margrave (1979), Mims (1979), Whitney (1979), Zissell (1979), Bruch (1980) and Belyakina et al. (1982) into our analysis. Observations made by Nakagiri and Yamashita (1980) were not included, because of large scatter. The computing code for period search Hec 18 (Harmanec, 1981) and code of Zverko (1981), which are based on Morbey's method (Morbey, 1978), were used to find the period. The best period is 78.12 days. The ephemeris is as follows: JD (Min) = 2443943.39 + 78.12d x E. (1) Phase in Table II is computed according to this ephemeris. As it is possible to see on the phase diagram of PU Vul (Fig. 1), the primary and secondary minima are well seen on the light curve. Chochol and Grygar (1982) propose binary model "down scaled" symbiotic to explain photometric and spectroscopic behaviour of PU Vul. D. CHOCHOL, L. HRIC J. PAPOUSEK Astronomical Institute of the Astronomical Institute Slovak Academy of Sciences of J.E. Purkyne University 059 60 Tatranska Lomnica 611 37 Brno Czechoslovakia Czechoslovakia References: Belyakina, T.S., Gershberg, R.E., Efimov, Yu.S., Krasnobabtsev, V.I., Pavlenko, E.P., Petrov, P.P., Chuvaev, K.K., Shenavrin, V.I. 1982, Astron. Zh. in press [BIBCODE 1982SvA....26..184B ] Bruch, A. 1980, Inform. Bull. Var. Stars No. 1805 Chochol, D., Grygar, J. 1982, IAU Colloq. No. 69, in press [BIBCODE 1982ASSL...98..473C ] Harmanec, P. 1981, private comm. Mahra, H.S., Joshi, S.C., Shrivastava, J.B., Dhir, S.L. 1979, Inform. Bull. Var. Stars No. 1683 Margrave, T.E. 1979, IAU Circ. No. 3421 [BIBCODE 1979IAUC.3421....2M ] Mims, S.S., Mullikin, T.L. 1979, IAU Circ. No 3380 [BIBCODE 1979IAUC.3380....3M ] Morbey, C.L. 1978, Publ. Dominion Astrophys. Obs. 15,105 [BIBCODE 1978PDAO...15..105M ] Nakagiri, M., Yamashita, Y. 1980. Tokyo Astron. Bull. 263, 2993 [BIBCODE 1980TokAB.263.2993N ] Whitney, C.A. 1979, IAU Circ. No. 3348. [BIBCODE 1979IAUC.3348....2A ] Zissell, R.E. 1979, IAU Circ.No.3355 [BIBCODE 1979IAUC.3355....2Z ] Zverko, J. 1981, private comm.