TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2061 SUBJECT: triangulation of GRB 030331 (single error box) DATE: 03/04/01 14:42:27 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, E. Mazets, V. Pal'shin, and D. Frederiks on behalf of Konus-Wind and Helicon/Coronas-F teams, T. Cline, on behalf of the Ulysses and Konus GRB teams, K. Hurley, on behalf of the Ulysses GRB team, and A. von Kienlin, G. Lichti, and A. Rau, on behalf of the INTEGRAL SPI-ACS GRB team, report: GRB 030331 was detected by Konus-Wind at 05:38:40.824 UT and Helicon-Coronas-F at 05:38:44.347 UT. As observed by Konus-Wind, it had a 15-2000 keV fluence of approximately 2.7E-5 erg/cm2 in 25 s, and a peak flux of 5.5E-6 erg/cm2 s over 0.128s. We have triangulated it to a preliminary annulus centered at RA(2000) = 27.250 deg, Decl(2000) = 13.733 deg, Radius = 40.7 +/- 1.1 degrees (3 sigma ). This annulus intersects the IPN annulus (GCN 2057) to form two large error boxes, only one of which is in the correct ecliptic latitude band. Preliminary 3 sigma error box has approximate area of 400 sq. arcmin : RA(2000) Dec(2000) ERROR BOX CENTER: 349.261 36.260 ERROR BOX CORNER 1: 347.872 36.429 ERROR BOX CORNER 2: 347.852 36.389 ERROR BOX CORNER 3: 350.666 36.089 ERROR BOX CORNER 4: 350.643 36.049 -- Dmitry Frederiks [aka Fred] ------------------------------------------------------- Lab for High Energy Astrophysics, Space Research Dept, A.F.Ioffe Phys.-Tech. Institute, St.Petersburg, Russia -------------------------------------------------------