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: 1112+48 XTE J1118+480 1140-03 TW VIR No. 600 0445-76 TU MEN 1147+49 BC UMA March 31, 2000 0846+58 BZ UMA 1841+37 AY LYR 1011+72 CI UMA ---------------------------------------------------------------------------- 1112+48 XTE J1118+480 We have been informed by the Central Bureau for Astronomical Telegrams (IAU Circular 7390) of the discovery of the probable optical counterpart of the Rossi X-Ray Timing Explorer (XTE) source J1118+480 by M. Uemura and T. Kato, Kyoto University, and H. Yamaoka, Kyushu University, Japan, on behalf of the VSNET collaboration team, Japan, on Mar. 30.726 UT at unfiltered CCD magnitude 12.92 using a Kyoto University 0.25-m telescope. The position of the probable optical counterpart was measured by Yamaoka and given as R.A. = 11h 18m 10.79s Decl. = +48 degrees 02' 11.2" (equinox 2000). Optical confirmation was obtained by D. Buczynski, Condor Brow Observatory, United Kingdom, who observed the object at unfiltered CCD magnitude 12.91 on Mar. 30.863 UT. An AAVSO preliminary chart will be issued on Monday, April 3. Congratulations to M. Uemura, T. Kato, and H. Yamaoka on their discovery! ---------------------------------------------------------------------------- 0445-76 TU MENSAE The dwarf nova type (SU UMA subclass) cataclysmic variable TU MEN appears to be in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAR 29.4444 <14.5 SRX MAR 30.7896 13.0 SRX MAR 30.7437 13.9 SRX MAR 30.7993 13.0 SRX MAR 30.7722 13.8 SRX ---------------------------------------------------------------------------- 0846+58 BZ URSAE MAJORIS The dwarf nova type (SU UMA subclass) cataclysmic variable BZ UMA may be in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAR 25.901 15.9 PYG MAR 28.919 <13.7 PYG MAR 26.009 <14.1 MGH MAR 28.927 <14.5 OJR MAR 26.863 <14.1 MUY MAR 31.2042 14.3 AAP MAR 27.2528 <15.8 HSG ---------------------------------------------------------------------------- 1011+72 CI URSAE MAJORIS The dwarf nova type cataclysmic variable CI UMA may be in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAR 25.904 <15.3 PYG MAR 28.922 <15.3 PYG MAR 26.915 <14.1 MUY MAR 31.0368 14.1 CGF ---------------------------------------------------------------------------- 1140-03 TW VIRGINIS The dwarf nova type cataclysmic variable TW VIR is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAR 27.2451 14.8: HSG MAR 30.2458 12.8 AAP MAR 27.4972 <14.3 SRX MAR 30.7403 13.6 SRX MAR 28.5646 14.2 SRX MAR 31.1326 13.2 MKJ MAR 29.4306 14.0 SRX ---------------------------------------------------------------------------- 1147+49 BC URSAE MAJORIS The dwarf nova type cataclysmic variable BC UMA is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAR 28.80 <13.7 SPK MAR 31.836 11.3 KTO MAR 31.799 12.1 SPK According to the AAVSO International Database this star is fainter than visual magnitude 19.0 during quiescence and was last in outburst in July 1995. ---------------------------------------------------------------------------- 1841+37 AY LYRAE The dwarf nova type (SU UMA subclass) cataclysmic variable AY LYR is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials MAR 24.3320 17.86 ZRE MAR 31.11 14.9 VER MAR 25.097 <15.3 PYG MAR 31.3380 14.13 CCDV ZRE MAR 26.088 <15.3 PYG ---------------------------------------------------------------------------- We thank the following contributors for the data that they have provided for this News Flash: AAP - A. ABBOTT, CANADA OJR - J. OSORIO, SPAIN CGF - G. CHAPLE JR., USA PYG - G. POYNER, ENGLAND HSG - G. HANSON II, USA SPK - P. SCHMEER, GERMANY MGH - H. MCGEE, ENGLAND SRX - R. STUBBINGS, AUSTRALIA MKJ - J. MCKENNA, USA VER - B. VAN DER ENDE, CANADA MUY - E. MUYLLAERT, BELGIUM ZRE - R. ZISSELL, USA Please monitor these and other variable stars closely and phone-in, fax, or e-mail your observations to the AAVSO. Good observing! Kerri Malatesta, Technical Assistant On behalf of Janet A. Mattei, Director ____________________________________________________________________________ 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! ____________________________________________________________________________