TITLE: GCN GRB OBSERVATION REPORT NUMBER: 568 SUBJECT: GRB000301C: RXTE/ASM and IPN localizations DATE: 00/03/02 19:25:31 GMT FROM: Don Smith at MIT GRB000301C D. A. Smith (MIT) reports on behalf of the ASM team at MIT and NASA/GSFC, and K. Hurley (UCB) and T. Cline (NASA/GSFC) report on behalf of the Ulysses and NEAR GRB teams: The ASM has detected a GRB at 03/01/2000 09:51:37 (UTC). The burst showed a single peak with a simple fast-rise, slow-decay structure. The three ASM energy channels showed the strongest response in the 5-12 keV band, reaching a peak flux of 3.7+-0.7 Crab (5-12 keV) in 1-s time bins. The event lasted approximately 10 seconds. The event was detected by a single ASM SSC, yielding an error box (90% confidence, including systematic and statistical error) 4.2 degrees long and 8.7 arcminutes wide, centered at R.A. = 16h 13m 14s and Decl. = 28o 37' 59.2" (J2000.0), with a position angle of -117.1 degrees. Ulysses and NEAR observed this burst. Preliminary triangulation gives an annulus 5' in full-width (3 sigma), centered at R.A. = 20h 34m 7.56s and Decl. = 20o 32' 19.62s (J2000.0), with a central radius of 57.520 degrees. This annulus may be refined. This annulus intersects the ASM error box at near-right angles to create a composite localization of a parallelogram of area ~50 sq. arcmin with the following corners (J2000.0): R.A. Decl. 16h 20m 30s +29o 30' 14.3" 16h 20m 08s +29o 27' 50.4" 16h 20m 13s +29o 19' 40.8" 16h 20m 35s +29o 22' 00.0" Figures and charts can be found at http://gx339.mit.edu/grb000301c/ This message may be cited.