BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.168 1998, September 27 Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM Internet: Tonny.Vanmunster@advalvas.be TEL. 32-11-831504 CVC Web Page : http://cba.phys.columbia.edu/cvc =================================================================== PU Per [UGSU:, 14.7p - 20:p] ============================ T. Kinnunen, Finland has reported his detection of an outburst of the CVAP object PU Per. Confirmation has been obtained from Jonathan Kemp (CBA New York), observing at MDM Observatory. 1998 Sep 22.880 UT, <15.0 (T. Kinnunen) Sep 24.919 UT, <15.0 (T. Kinnunen) Sep 25.871 UT, 14.8 (T. Kinnunen) Sep 26.522 UT, 14.76 (J. Kemp, V-filter, MDM Obs) Sep 26.926 UT, 14.8 (T. Vanmunser, unfiltered) PU Per is a dwarf nova with rare outbursts : the last one was observed in October 1995 [CVC 62] by M. Iida, and was a very faint one, at mag. V = 16.5 [CVC 63]. During that outburst, T. Kato and his team at Ouda Observatory reported the detection of low-amplitude hump-like features, with a rough period of 0.058 +/-0.002 day. We have been able to obtain unfiltered CCD observations last night, at CBA Belgium Observatory, using a 0.25-m f/6.3 telescope (September 26/27, 1998 ), under poor conditions (many clouds), during 3.6h. The resulting light curve doesn't show superhumps or evident hump-like features. It only includes some small variations (of approx. 0.1 mag), for which no definite periodicity could be derived (yet). Evidently, this doesn't imply that the current outburst can't be a superoutburst : it may be that superhumps still have to emerge. Continued CCD time-resolved photometry is strongly encouraged. Tonny Vanmunster