TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2501 SUBJECT: GRB031225a triangulation (annulus) DATE: 03/12/26 16:17:19 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 Konus GRB team, GRB031225a was detected by Konus-Wind at 08:52:41.089 UT and Helicon-Coronas-F at 08:52:40.131 UT. It has a duration of ~80 sec. We have triangulated it to a preliminary annulus centered at RA(2000) = 270.474 deg, Decl(2000) = -19.720 deg, Radius = 83.0 +/- 1.5 degrees (3 sigma ).