BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.146 1997, August 22 Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM Internet: tvanmuns@innet.be TEL. 32-11-831504 CVC Web Page : http://www.astro.columbia.edu/~cba/cvc =================================================================== V337 Cyg [UG:, 14.4p - <16.5p] ============================== Jan Manek, Stefanik Observatory, Czech Republic, reports his detection by CCD of an outburst of this very interesting dwarf nova, which is part of the Belgian Cataclysmic Variables Alert Programme (CVAP). Lasse Jensen, CBA Denmark has been able to confirm the outburst. The available observations are as follows : 1997 Aug 15.966 UT, <14.4 (G. Poyner, 0.40-m refl., visual); Aug 19.873 UT, <16.3 (T. Vanmunster, 0.25-m refl., unfilt CCD); Aug 20.951 UT, 15.60V (J. Manek, 0.65-m refl., CCD+V); Aug 21.849 UT, 15.7 (L. Jensen, 0.25-m refl., unfilt CCD); V337 Cyg was discovered by Walter Baade in 1928 (Astron. Nach. 232, 65). Jan Manek apparently already studied V337 Cygni's outburst behaviour in quite some detail back in 1996. In a September 1996 VSNET message he wrote, as a result of a screening he did of plates in the Sonneberg plate archive : "I have found V337 Cyg in at least 3 outbursts, being usually less than 5 days long and reaching about mag 15 in maximum on blue plates. In minimum it is below the plate limit (< 18 mag pg). Plate scans were made for both (maximum and minimum) states." Manek later announced 3 more outbursts on archive plates and noticed a recurrence period of about 32 days. Accurate astrometry by Manek reveals following coordinates (J2000.0) : R.A. = 19h59m52.96s, Decl.= +39d13'59.8". Since previous outbursts of V337 Cyg have not been studied in detail, it is of extreme importance to monitor the present outburst as intensively as possible. Tonny Vanmunster