BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.96 1996, May 26 Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM Internet: tvanmuns@innet.be TEL. 32-11-831504 -------------------------------------------------------------- The CATACLYSMIC VARIABLES Home Page: http://www.cv.psi.edu =================================================================== V1316 Cyg [UGSU:, 14.5p - <17.5p] ================================= We have received a number of follow-up observations for the outburst of this interesting dwarf nova, announced in CVC 95, including a time-series photometry session, obtained by Lasse Jensen, CBA Denmark, on the night of May 6/7, 1996 (of which some samples are reproduced below). There are some remarkable observations in the photometric summary below, which suggest a large difference between visual and infrared (CCD) appearance of the object, and which might indicate that the outburst seen on April 27th [CVC 92] in fact is still ungoing ! It is evident that a further photometric coverage of this object is highly desirable, both at visual and infrared wavelengths. ----------------------------------------------------------------------- DATE (UT) MAGN MS SEQ OBSERVER REMARKS SOURCE ----------------------------------------------------------------------- 1996 04 22.021 [14.9 mv Kat Poyner, G. CVC 92 1996 04 27.052 14.7 mv Kat Poyner, G. CVC 92 1996 04 27.092 14.6 mv Kat Poyner, G. CVC 92 1996 04 28.035 14.7 mv Kat Poyner, G. CVC 92 1996 04 29.919 14.7 CU Kat Vanmunster, T. CVC 92 1996 04 30.028 14.9 mv Kat Poyner, G. CVC 92 1996 04 30.998 14.2 CU Kat Jensen, L. CVC 92 1996 05 05.024 [14.8 mv Kat Poyner, G. CVC 92 1996 05 06.938 14.4 CU Kat Jensen, L. 1996 05 06.989 14.5 CU Kat Jensen, L. 1996 05 07.006 14.3 CU Kat Jensen, L. 1996 05 07.006 14.3 CU Kat Jensen, L. 1996 05 07.050 14.3 CU Kat Jensen, L. 1996 05 07.075 14.3 CU Kat Jensen, L. 1996 05 08.010 [14.8 mv Kat Poyner, G. CVC 92 1996 05 08.067 14.3 CU Kat Jensen, L. 1996 05 14.034 14.3 CU Kat Jensen, L. 1996 05 15.031 [14.8 mv Kat Poyner, G. CVC 92 1996 05 16.079 [14.3 mv Kat Poyner, G. CVC 92 1996 05 19.095 14.1 CU Kat Vanmunster, T. CVC 95 1996 05 20.047 14.2 CU Kat Vanmunster, T. 1996 05 20.992 14.4 CU Kat Vanmunster, T. 1996 05 22.006 14.5 CU Kat Vanmunster, T. 1996 05 23.028 14.1 CU Kat Jensen, L. 1996 05 25.075 [14.1 mv Kat Poyner, G. V632 Cyg [UGSS, 12.6p - 17.5p] ============================== Gary Poyner, Birmingham, UK writes, in response to an observation of this object by the undersigned : "Regarding your May 19.017 UT obser- vation of V632 Cyg, I think that this must be a seperate outburst [from the one announced in CVC 94, ed.]. My observations show the object had faded below mag 15.3 on May 16.084 UT. Has the May 13 outburst triggered a supermaximum, or will it fade quickly? I cannot remember two outbursts occuring so close together in this star before." We have summarized the photometric behaviour of V632 Cyg (observa- tions since May 6, 1996) in the table below. Tonny Vanmunster, CBA Belgium, obtained a time-series photometry of V632 Cyg (using a 0.25-m SCT and ST-7 CCD) on May 21/22. The final reduction of the images has not been completed yet. Results will be communicated later on. ----------------------------------------------------------------------- DATE (UT) MAGN MS SEQ OBSERVER REMARKS SOURCE ----------------------------------------------------------------------- 1996 05 06.075 [15.7 mv Vanmunster, T. CVC 94 1996 05 07.055 [14.6 mv Poyner, G. CVC 94 1996 05 13.052 13.9 mv Poyner, G. CVC 94 1996 05 14.065 14.2 mv Poyner, G. CVC 94 1996 05 15.047 14.8 mv Poyner, G. 1996 05 16.084 [15.3 mv Poyner, G. 1996 05 18.96 13.8 mv Szentasko, L. 1996 05 19.017 14.1 mv AAV Vanmunster, T. 1996 05 19.018 14.3 CV Vanmunster, T. Approx. V mag 1996 05 19.965 14.4 mv AAV Vanmunster, T. 1996 05 20.996 15.1 CU Vanmunster, T. poor conditions 1996 05 21.94 14.5 mv Szentasko, L. 1996 05 22.008 14.8 CU Vanmunster, T. 1996 05 23.034 15.1 CU Jensen, L. 1996 05 25.058 [14.3 mv Poyner, G. 1996 05 25.238 [14.1 mv AAV Stewart, R. V630 Cyg [UGSU:, 13.4p - 17.2p] =============================== Lasse Jensen, Farum, Denmark has detected an outburst of this CVAP object, using a 0.25-m SCT and ST-7 CCD, at the CBA Denmark. His observation is reproduced below. Please remark that the classification of V630 Cyg as an UGSU object is still unsure. Follow-up observations therefore are highly encou- raged. 1996 May 23.041 UT, 15.5 (L. Jensen, 0.25-m SCT, ST-7 CCD); May 25.063 UT, [14.1 (G. Poyner, 0.40-m refl.); May 25.239 UT, [14.1 (R. Stewart, USA); The previous outburst of V630 Cyg was seen October 25, 1995 [CVC 66] by E. Broens, Belgium. It was separated by only 4 days from an earlier outburst observation [CVC 65] by T. Vanmunster, Belgium. BZ UMa [UGSU:, 10.5v - 17.8v] ============================= The outburst of BZ UMa, announced in CVC 94, clearly was a normal one, as indicated by the table of observations below. The object has returned to quiescence. ----------------------------------------------------------------------- DATE (UT) MAGN MS SEQ OBSERVER REMARKS SOURCE ----------------------------------------------------------------------- 1996 05 13.207 [13.7 mv Burrows, T. CVC 94 1996 05 13.890 [13.7 mv Jensen, L. 1996 05 14.006 [13.7 mv Poyner, G. CVC 94 1996 05 14.215 [14.5 mv Hanson, G. CVC 94 1996 05 14.215 13.7 mv Burrows, T. CVC 94 1996 05 14.271 12.6 mv Burrows, T. CVC 94 1996 05 14.306 12.3 mv Burrows, T. CVC 94 1996 05 14.326 11.9 mv Burrows, T. CVC 94 1996 05 14.914 10.7 mv Poyner, G. 1996 05 14.951 10.7 mv Poyner, G. 1996 05 14.976 10.6 mv Poyner, G. 1996 05 14.999 10.6 mv Poyner, G. 1996 05 15.024 10.7 mv Poyner, G. 1996 05 15.06 10.8 mv Dyck, G. 1996 05 15.078 11.2 mv Mc Kenna, J. 1996 05 15.4355 11.87 CV Ouda Station 1996 05 15.4359 12.00 CV Ouda Station 1996 05 15.4365 11.89 CV Ouda Station 1996 05 15.4369 11.99 CV Ouda Station 1996 05 15.4373 12.00 CV Ouda Station 1996 05 15.4677 11.42 CU Iida, M. 1996 05 15.594 12.1 mv Watanabe 1996 05 16.028 11.9 mv Poyner, G. 1996 05 16.168 11.9 mv York, D. 1996 05 16.229 11.8 mv Hanson, G. 1996 05 16.4418 12.93 CV Ouda Station 1996 05 16.4427 12.99 CV Ouda Station 1996 05 16.4441 12.95 CV Ouda Station 1996 05 16.4458 13.08 CV Ouda Station 1996 05 16.992 14.1 CU Vanmunster, T. 1996 05 17.0424 12.8 mv Brincat, S. 1996 05 18.446 15.22 CV Ouda Station 1996 05 18.919 15.3 CU Vanmunster, T. 1996 05 18.996 15.0 mv Vanmunster, T. 1996 05 18.9 15.7 mv Szentasko, L. 1996 05 24.926 [13.7 mv Poyner, G. Tonny Vanmunster