THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS 25 Birch Street, Cambridge, MA 02138 USA Tel. 617-354-0484 Fax 617-354-0665 http://www.aavso.org * * * AAVSO NEWS FLASH * * * Subject: MAGNETIC CATACLYSMIC VARIABLES No. 703 1953+77 AB DRA 2335+12 HX PEG November 29, 2000 ---------------------------------------------------------------------------- MONITORING MAGNETIC CATACLYSMIC VARIABLES (POLARS) Astronomers at Planetary Science Institute and University of Florida have an observing run at Mauna Kea, Hawaii using the UK's Infrared Telescope (UKIRT) to monitor the following magnetic cataclysmic variables - subclassed as Polars. These cataclysmic variables, like AM Her, have magnetic fields of the primary (the white dwarf) strong enough to control the accretion flow and disrupt the accretion disk. In their light variation they show "down" (faint) and "up" (bright) states. Our colleagues have requested that our CCD observers and visual observers with large aperture telescopes monitor these stars starting tonight for a week and inform us of their observations. Desig Name R.A. Decl. Type Max Min (J2000) (J2000) Mag Mag 0309-22 EF Eri 03 14 13.03 -22 35 41.4 AM 14.5B 17.3B 0331-26 UZ For 03 35 28.61 -25 44 22.6 AM 18.2V 20.9V 0533+60 BY Cam 05 42 48.90 60 51 31.8 AM 15.25B 17B 0810-18 VV Pup 08 15 06.73 -19 03 16.8 AM 13.9V 18V 1813+49 AM Her 18 16 13.33 49 52 04.2 AM 12.3V 15.7V AM Her is in the regular AAVSO observing program. AAVSO preliminary charts are available for this variable via the AAVSO web page. For the other four polars (EF ERi, UZ For, BY Cam, and VV Pup) we have placed finder charts with preliminary sequences on our web page at the following address http://www.aavso.org/newsflash/cvcharts.stm Please observe as many of the above polars as you can, and send us your observations so that our colleagues can determine whether these stars are in their "up" or "down" states. ---------------------------------------------------------------------------- 1953+77 AB DRACONIS The dwarf nova type (Z CAM subclass) cataclysmic variable AB DRA is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials NOV 26.740 14.7 PYG NOV 27.841 13.4 RMQ NOV 26.744 14.3: MUY NOV 28.878 12.9 MUY ---------------------------------------------------------------------------- 2335+12 HX PEGASI The dwarf nova type cataclysmic variable HX PEG is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials NOV 26.839 15.6 PYG NOV 28.871 13.2 MUY NOV 27.457 14.5 SRX ---------------------------------------------------------------------------- We thank the following contributors for the data that they have provided for this News Flash: MUY - E. MUYLLAERT, BELGIUM RMQ - M. RESZELSKI, POLAND PYG - G. POYNER, ENGLAND SRX - R. STUBBINGS, AUSTRALIA Please monitor these and other variable stars closely and phone-in, fax, or e-mail your observations to the AAVSO. Good observing! Janet A. Mattei, Director Rebecca Pellock, Technical Assistant ____________________________________________________________________________ Symbols may include: < = fainter than magnitude given (variable not seen) : = uncertain CCDV = Charge-coupled device with (V) filter If you would like to contribute to AAVSO NEWS FLASH, please send observations of unusual variable star activity to: observations@aavso.org Those who wish to subscribe (free of charge) or unsubscribe to NEWS FLASH may do so by visiting the following web page: http://www.aavso.org If you would like data from the AAVSO International Database for research purposes, please send your request to: Janet Mattei, AAVSO Director, at aavso@aavso.org An archive of past issues of the News Flash is available at the following web page: http://www.aavso.org/newsflash/ We look forward to including your observations in future editions of AAVSO NEWS FLASH! ____________________________________________________________________________