BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.103 1996, August 12 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 =================================================================== V725 Aql [UG, 13.7p - [19?p] ============================= We have been informed by Gary Poyner, Birmingham, UK about the visual detection by J. Day, UK of an outburst of the interesting dwarf nova V725 Aql, which is part of the TA/BAAVSS Recurrent Objects Programme. Gary has confirmed the event. Here are the details : 1996 Aug 09.892 UT, [16.5 (T. Vanmunster, unfilt. CCD image); Aug 12.890 UT, 13.5 (J. Day, seq: TA); Aug 12.903 UT, 13.4 (G. Poyner, seq: TA); According to the "Outburst Activity Database on Selected Cataclysmic Variables", V725 Aql was last reported in outburst on 1995, March 8 by the Ouda Team of Kyoto University, Japan, at mag 13.5. Remark that the position indicated in the Downes & Shara atlas is incorrect. During the March 1995 outburst of V725 Aql, M. Iida, VSOLJ, Japan, reported following astrometric results : R.A. = 19h56m45s.03, decl.= +10d49'32".7 (J2000.0) (+/-0.5 arcsec). V630 Cyg [UGSU:, 13.4p - 17.2p] =============================== P. Skalak, Czech Republic, reports his visual detection of an outburst of the CVAP object V630 Cyg. He observed it on the evening of August 10, 1996 at mag. 14.5. An independent outburst detection has also been reported by Marc Biesmans, Essen, Belgium. Confirmative observations have been received from Tonny Vanmunster (CCD), Gary Poyner (visual) and D. Nogami (CCD). 1996 Aug 07.962 UT, [15.2 (G. Poyner, 0.40-m refl.); Aug 10. UT, 14.5 (P. Skalak, seq: AAVSO); Aug 11.905 UT, 14.8 (T. Vanmunster, 0.25-m SCT, unfilt. CCD image); Aug 11.944 UT, 14.0 (G. Poyner); Aug 12.027 UT, 14.4 (M. Biesmans, 0.30-m SCT); We again would like to stress that the classification of V630 Cyg as a SU UMa-type dwarf nova is still unsure. Therefore follow-up observations (in particular time-series CCD photometry in search of superhumps), are highly encouraged. V630 Cyg was last seen in outburst on July 10, 1996 by E. Broens [CVC 99]. This was a normal, faint outburst [CVC 101]. V1028 Cyg [UGSU, 13.0p - 18p] ============================= This interesting object, reported in outburst in CVC 102, started to fade rather quickly, leading to the conclusion that this time we were observing a normal outburst of this SU UMa-type dwarf nova. However, a re-brightening of V1028 Cyg has been reported by Marc Biesmans, Essen, Belgium and subsequently confirmed by D. Nogami, Ouda Team, Kyoto University, Japan. Therefore, the normal outburst presumably has been a pre-trigger for a superoutburst, which very likely just has started. Again, time-series CCD photometry is highly encouraged. 1996 Aug 05.880 UT, [16.6 (T. Vanmunster, CBA Belgium, unfilt.CCD exp); Aug 07.048 UT, [15.6 (M. Biesmans, Belgium); Aug 07.899 UT, 13.6 (M. Biesmans); Aug 07.86 UT, 14.1 (J. Pietz); Aug 07.87 UT, 14.0 (J. Pietz); Aug 07.90 UT, 14.0 (J. Pietz); Aug 07.93 UT, 13.9 (J. Pietz); Aug 07.96 UT, 13.9 (J. Pietz); Aug 08.028 UT, 13.5 (M. Biesmans); Aug 08.50 UT, 13.95 (Ouda Team, Kyoto University, CCD+V); Aug 08.883 UT, 14.9 (T. Vanmunster, CCD unfiltered); Aug 08.89 UT, 14.5 (J. Pietz); Aug 11.995 UT, 13.5 (M. Biesmans); Aug 12.523 UT, 13.61 (Ouda Team, Kyoto University, CCD+V); WX Cet [UGWZ, 9.5v - 17.5v] =========================== Another story of a re-brightening ! After the recent superoutburst of WX Cet, this object was well on its way back to minimum light, when two observation teams independently reported the start of a new bright phase in the outburst light curve. The Ouda Team of Kyoto University, Japan and CBA member Jonathan Kemp, Columbia University, NY, observing from Cero Tololo, Chile, detected this re-brightening. Some selected observations (see also CVC 102) : 1996 Jul 19.463 UT, 12.2 (L. Shaw, USA, seq.: AAVSO); Jul 18.38 UT, 11.87 (J. Kemp, CTIO); Jul 19.35 UT, 11.95 (J. Kemp, CTIO); Jul 20.38 UT, 12.12 (J. Kemp, CTIO); Jul 21.33 UT, 12.32 (J. Kemp, CTIO); Jul 22.37 UT, 12.48 (J. Kemp, CTIO); Jul 23.37 UT, 12.65 (J. Kemp, CTIO); Jul 27.73 UT, 12.98 (Ouda); Jul 29.72 UT, 13.25 (Ouda); Jul 30.78 UT, 13.88 (Ouda); Jul 31.78 UT, 14.85 (Ouda); Aug 02.77 UT, 15.45 (Ouda); Aug 05.77 UT, 16.50 (Ouda); Aug 06.35 UT, 16.70 (J. Kemp, CTIO); Aug 07.81 UT, 15.45 (Ouda); Aug 08.29 UT, 13.85 (J. Kemp, CTIO); Aug 08.79 UT, 14.15 (Ouda); Aug 09.27 UT, 15.19 (J. Kemp, CTIO); Aug 09.42 UT, 15.57 (J. Kemp, CTIO); Aug 11.71 UT, 17.17 (Ouda); Further comments on this object were recently communicated by Joe Patterson and Jonathan Kemp, Columbia University, NY, as follows : "A common superhump of 85.5 min was seen during the bright phase of the eruption. A dwarf nova oscillation was seen at 17.38 seconds on July 23. A "second peak" was seen to occur at about August 8.2 (previously noted by Nogami & Baba, vsnet-alert 502). The light then declined rapidly at 1.5 mag/d, a rate characteristic of the "normal maxima" of short-Porb dwarf novae. On all three nights of the CTIO August coverage, a quasi-periodic oscillation with P=9-10 min was observed." Tonny Vanmunster