(fwd) RXTE observations of YY (DO) Dra From: Koji Mukai <mukai@milkyway.gsfc.nasa.gov> Subject: RXTE observations of YY (DO) Dra Date: Fri, 17 Nov 2000 13:45:22 -0500 (EST) Northern Observers, We have been granted TOO observation of YY (DO) Dra with the RXTE satellite during the current outburst, as follows (all times UT). Nov 19 00:34-01:35 02:14-03:16 03:54-04:51 Nov 20: 00:27-01:28 02:06-03:08 03:47-04:43 22:40-23:42 Nov 21: 00:20-01:22 01:58-03:00 We hope to be able to track the X-ray flux and X-ray spin pulse shapes in decline (unfortunately, spacecraft safety concerns during the Leonids have prevented earlier RXTE observations --- but we'll still get good data). Dr. Szkody has pointed out that, during the last outburst, X-ray and optical spin pulses were out of phase. We would therefore like to request all observers capable of fast photometry to obtain as much data as weather etc. permit --- this system has a 530 s spin period, but most of the modulations are at 1/2 the spin period and its orbital sideband. Simultaneous photometry with RXTE would be particularly valuable; even if not simultaneous, any data that would allow us to track the evolution of spin modulation during the outburst decay would be highly useful. Best wishes, Koji Mukai (mukai@milkyway.gsfc.nasa.gov)