BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.78 1996, January 19 Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM Internet: tvanmuns@innet.be TEL. 32-11-831504 -------------------------------------------------------------- The CATACLYSMIC VARIABLES Home Page: hht://www.cv.psi.edu =================================================================== S10932 [UG:+E, 13.4 - 18.5p] ============================ This interesting eclipsing dwarf nova (CVAP object) has been monitored in close detail during its past outburst (announced in CVC 77). It seems this was a normal outburst, given the short duration and rapid fading, and the apparent lack of superhump observations. Observed eclipses sometimes were very deep (up to 3.2 mag V, as reported by T. Kato and the Ouda Team, Kyoto University, Japan). This is one of the deepest known eclipse amplitudes known among outbursting dwarf novae. Kato further measured the duration of eclipses (which is nearly 10 minutes). Similar deep eclipses were also reported by German astronomers Peter Kroll and Gerold Richter of Sonneberg Observatory, who measured an amplitude of about 4.4 mag (R band). We received following observations of S10932 : ----------------------------------------------------------------------- DATE (UT) MAGN MS SEQ OBSERVER REMARKS SOURCE ----------------------------------------------------------------------- 1995 12 29.022 [14.1 mv GSC Vanmunster, T. CVC 77 1996 01 01.83 13.5 CV Kato, T. & Ouda Team CVC 77 1996 01 02.817 14.5 mv VS Koshiro, M. VSNET 1996 01 02.89 14.8 CV Kato, T. & Ouda Team VSNET 1996 01 03.865 [13.6 mv Makiguchi, N. VSNET A serious effort was made by Kato and his team to determine the precise mid-eclipse times of S10932. The following ephemeris has been derived after many successive refinements. It was published in a VSNET message dd. January 10, 1996 : Min.HJD = 2441798.44270 + 0.08703867378 E' Shortly before, Peter Kroll and Gerold A. Richter of Sonneberg Observatory, Germany, announced in a January 9, 1996 VSNET message : "The current out- burst of S10932 led us to (re)analyse CCD observations made at Sonneberg Observatory with a 60-cm-Cassegrain telescope from 1994, May 11 to 1996, Jan 04. Eclipsing times published in "Wenzel, Richter, Luthardt, Schwartz: IBVS 4182" are now improved. Using these minima times, which are distributed over more than 20 years, and the eclipsing times published on VSNET by Taichi Kato & Ouda team, we could derive the following ephemerides: Min (HJD) = J.D. 2449486.48166 + 0.0870386727 * E". V701 Tau [UGSU, 15.0p - <21p] ============================= This is another interesting CVAP object, that recently was discovered in outburst (see CVC 76). The photometric summary below concludes our monitoring action of this variable. It probably is for the first time in the history of V701 Tau that such an intensive photometry took place. ----------------------------------------------------------------------- DATE (UT) MAGN MS SEQ OBSERVER REMARKS SOURCE ----------------------------------------------------------------------- 1995 12 24.951 [15.6: mv GSC Vanmunster, T. CVC 75 1995 12 25.847 14.5 mv GSC Vanmunster, T. CVC 75 1995 12 25.866 14.5 mv GSC Poyner, G. CVC 75 1995 12 25.951 14.4 mv GSC Vanmunster, T. CVC 75 1995 12 25.983 14.1 mv GSC Broens, E. CVC 75 1995 12 26.552 14.4 CV *Kato & Ouda Team VSNET 1995 12 26.951 14.4:: mv GSC Poyner, G. VSNET 1995 12 27.023 14.5: mv GSC Broens, E. VSNET 1995 12 27.577 14.6 CV *Kato & Ouda Team VSNET 1995 12 27.903 [14.3 mv GSC Broens, E. VSNET 1995 12 27.957 14.4 mv GSC Pietz, J. VSNET 1995 12 28.934 [14.3 mv GSC Broens, E. VSNET 1995 12 28.940 14.6 mv GSC Pietz, J. VSNET 1995 12 28.985 14.7 mv GSC Vanmunster, T. VSNET 1995 12 29.566 14.6 CV *Kato & Ouda Team VSNET 1995 12 29.772 [14.3 mv GSC Poyner, G. VSNET 1995 12 29.845 14.8 mv GSC *Pietz, J. VSNET 1995 12 30.453 14.8 CV *Kato & Ouda Team VSNET 1995 12 31.527 14.9 CV *Kato & Ouda Team VSNET 1996 01 02.448 15.1 CV *Kato & Ouda Team VSNET 1996 01 07.496 15.6 CV *Kato & Ouda Team VSNET 1996 01 07.813 [14.3 mv GSC *Poyner, G. VSNET 1996 01 12.656 18.6 CV *Kato & Ouda Team VSNET 1996 01 13.521 19.5 CV *Kato & Ouda Team VSNET FS Aur [UGZ:, 14.4v - 16.2v] ============================ We received two additional observations, related to the December 1995 outburst of FS Aur (CVC 74) : 1996 01 01.422 UT, 16.8 (M. Iida, Japan, 20-cm refl.+CCD, unfiltered); 01 01.442 UT, 15.6 (M. Iida); UNCONFIRMED OUTBURST OBSERVATIONS ================================= Two CVAP objects recently have been reported in outburst, for which insufficient confirmative observations were available to generate a CVC. It concerns : TW Tri [UGZ, 13.3p - 17.0p] --------------------------- Reported in outburst by M. Iida, Japan, on 1996, January 1.445 UT, using a 20-cm reflector with CCD (unfiltered), at mag 14.9. The previous outburst of TW Tri was also detected by M. Iida, on 1995, November 12 (CVC 70). The following visual observation, reported by M. Moriyama, Japan relates to that outburst : 1995 Nov 15.588 UT, 14.2: TU Tri [UG, 14.8p - <18.0p] --------------------------- Also detected in outburst by Makoto Iida, Nagano, Japan, who recorded it on an unfiltered CCD image on 1996, Jan. 1.455 UT at mag. 15.8. We have created a GSC-based sequence (and corresponding large scale finder chart) of TU Tri, which you may obtain at the Cataclysmic Variables Home Page. Tonny Vanmunster