Circular No. 5437 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION Postal Address: Central Bureau for Astronomical Telegrams Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Telephone 617-495-7244/7440/7444 (for emergency use only) TWX 710-320-6842 ASTROGRAM CAM EASYLINK 62794505 MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN SUPERNOVA 1992B IN ANONYMOUS GALAXY C. Pollas, Observatoire de la Cote d'Azur, reports his discovery of an apparent supernova (mpv = 17.8) found on technical pan films taken on Jan. 14.2 and 15.2 UT. SN 1992B is located at R.A. = 11h13m17s.03, Decl. = +55 45'52".9 (equinox 1950.0), or 12".7 east and 4".5 north of the nucleus of a spiral galaxy of mag 16.5. A nearby star of mag 16 has end figures 13s.50, 54".5. The limiting magnitude of the films is 22, and nothing is seen on the POSS prints (limiting mpv = 20.5). GRS 0834-430 R. Sunyaev, S. Grebenev, M. Dennis, and A. Goldwurm, on behalf of the Granat team (Space Research Institute, Moscow; Service d'Astrophysique, Centre d'Etudes Nucleaires de Saclay; Centre d'Etude Spatiale des Rayonnements, Toulouse), report: "The transient x-ray pulsar GRS 0834-430 (IAUC 5139, 5142, 5180, etc.) was observed with instruments onboard Granat on 1991 Dec. 18 and was found to be in a bright state. Its x-ray flux was 94 +/- 4 and 174 +/- 8 mCrab in the ART-P 6- to 15-kev and 15- to 35-keV energy bands and 44 +/- 8 mCrab in the SIGMA 35- to 100-keV band. The source had a power-law spectrum with a photon index of -1.04 +/- 0.03, which cut off abruptly at energies > 30 keV; in the 35- to 100-keV bands, the photon index was about -4.7 +/- 1.0. The barycentric period of x-ray pulsations was found to be 12.3073 +/- 0.0001 s (on Dec. 18.6 UT), indicating that the pulsar continued to spin up with period derivative P-dot/P about -1.7 x 10E-3 yrE-1 (IAUC 5294). The 1991 December outburst became the fifth x-ray outburst detected from GRS 0834-430 since its discovery by the WATCH instrument onboard Granat in 1990 February (IAUC 5122)." NOVA PUPPIS 1991 Visual magnitude estimates (cf. IAUC 5423): Jan. 10.642 UT, 8.8 (S. Sakuma, Kawasaki, Japan); 12.1, 9.0 (J. Smit, Waverly, South Africa); 13.184, 8.9 (P. Steffey, Daytona Beach, FL); 14.16, 8.6 (M. Adams, Melbourne, FL); 15.55, 9.2 (A. Pearce, Scarborough, W. Australia); 18.8, 9.2 (Smit); 19.25, 9.1 (R. Hays, Worth, IL); 20.35, 9.1 (R. Royer, Lakewood, CA); 22.53, 9.5 (Pearce). 1992 January 23 (5437) Daniel W. E. Green
Our Web policy. Index to the CBAT/MPC/ICQ pages.