TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3380 SUBJECT: GRB 050509a: Swift XRT Position DATE: 05/05/09 04:33:55 GMT FROM: Jamie A. Kennea at PSU/Swift-XRT J. A. Kennea, D. N. Burrows (PSU), C. P. Hurkett, E. Rol (U. Leicester) and N. Gehrels (NASA/GSFC) report on behalf of the Swift XRT team: The Swift BAT instrument detected GRB 050509a at 01:46:28 UT on 9th May 2005 (GCN Circ 3379). The observatory executed an automated slew to the BAT position and the XRT began taking data at 01:47:22 UT. The XRT was in Auto state but was not able to centroid on the afterglow due to low source intensity. From downlinked data we find a uncatalogued X-ray source located at: RA(J2000) = 20:42:19.7, Dec(J2000) = +54:04:16.2 We estimate an uncertainty of about 6 arcseconds radius (90% containment). This position is 13 arcseconds from the BAT position reported in GCN 3379.