TITLE: GCN GRB OBSERVATION REPORT NUMBER: 529 SUBJECT: IPN localization of GRB000131 DATE: 00/02/02 23:36:17 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley, on behalf of the Ulysses GRB team, and T. Cline and E. Mazets, on behalf of the KONUS-WIND and NEAR GRB teams, report: Ulysses, Konus, and NEAR observed a gamma-ray burst on January 31, 2000 at 14:59:13 UT. Its T90 duration was ~50 s and its 25-100 keV fluence was ~10^-5 erg/cm^2. At present, it can only be localized to two alternate ~55 sq. arcmin. error boxes given by the following preliminary centers and corners (~3 sigma confidence): ERROR BOX CENTER: 6 h 13 m 32.72 s -51 o 55 ' 36.77 " ERROR BOX CORNER 1: 6 h 13 m 8.83 s -52 o 2 ' 20.83 " ERROR BOX CORNER 2: 6 h 13 m 25.43 s -51 o 50 ' 11.43 " ERROR BOX CORNER 3: 6 h 13 m 40.09 s -52 o 1 ' 1.94 " ERROR BOX CORNER 4: 6 h 13 m 56.59 s -51 o 48 ' 52.07 " OR ERROR BOX CENTER: 10 h 48 m 50.99 s 4 o 34 ' 1.70 " ERROR BOX CORNER 1: 10 h 49 m 21.03 s 4 o 35 ' 42.55 " ERROR BOX CORNER 2: 10 h 48 m 31.31 s 4 o 36 ' 35.98 " ERROR BOX CORNER 3: 10 h 49 m 10.65 s 4 o 31 ' 26.95 " ERROR BOX CORNER 4: 10 h 48 m 20.91 s 4 o 32 ' 19.87 " There is a fair chance that further processing will allow one of these positions to be ruled out.