TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5313 SUBJECT: Swift trigger 219136 is probably not a GRB DATE: 06/07/14 17:51:58 GMT FROM: Scott Barthelmy at NASA/GSFC H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), D. N. Burrows (PSU), M. Capalbi (ASDC), M.L. Conciatore (ASDC), J. R. Cummings (NASA/UMD), C. Gronwall (PSU), C. Guidorzi (Univ Bicocca&INAF-OAB), J. A. Kennea (PSU), K. M. McLean (LANL/UTD), D. M. Palmer (LANL), M. Perri (ASDC), P. Romano (INAF-OAB), M. Stamatikos (NASA/ORAU) and L. Vetere (ASDC) report on behalf of the Swift Team: At 17:26:13 UT, the Swift Burst Alert Telescope (BAT) triggered on what is probably a cosmic ray particle event. However until we receive the full BAT event data set (in over three hours) we cannot definitively rule out this being a short GRB. The BAT on-board calculated location is RA,Dec 279.037,-42.733 {18h 36m 09s, -42d 43' 57"} (J2000) with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). This is a weak event and the currently available BAT light curve does not show much structure. Because of an Earth limb constraint, the spacecraft did not slew promptly to the BAT position, and so there are no immediate XRT and UVOT data products to analyze. The field will become visible to the Narrow Field Instruments at 18:28 UT.