TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3550 SUBJECT: GRB050525a: HST Observations DATE: 05/06/16 15:43:35 GMT FROM: Alicia Soderberg at Caltech A. M. Soderberg (Caltech) reports on behalf of the Caltech-NRAO-Carnegie collaboration: "We observed the field of GRB050525a (GCN 3466) with HST+ACS/WFC on 12 Jun 2005 UT (t~18 days) as part of our HST Cycle 13 program to study the supernovae associated with gamma-ray bursts and X-ray flashes (GO 10135; PI Kulkarni). Coincident with the afterglow position (GCN 3468), we detect a point source superposed on top of a compact galaxy. Within a 0.5 arcsec aperture, we find the host+OT system to be F625W ~ 24.2 mag (Vega). Adopting this value as a limit on the brightness of an associated supernova, we find that the SN associated with GRB050525a is at least ~0.6 magnitudes fainter than SN1998bw at a comparable epoch (assuming negligible host extinction). Further observations are planned."