TITLE: GCN CIRCULAR NUMBER: 12667 SUBJECT: GRB 111212A: Swift detection of a burst DATE: 11/12/12 09:41:19 GMT FROM: David Palmer at LANL S. Campana (INAF-OAB), J. R. Cummings (NASA/UMBC), V. D'Elia (ASDC), P. A. Evans (U Leicester), B. Gendre (ASDC), C. Guidorzi (U Ferrara), O. M. Littlejohns (U Leicester), A. Melandri (INAF-OAB), P. T. O'Brien (U Leicester), C. Pagani (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU), C. A. Swenson (PSU), E. Troja (NASA/GSFC/ORAU) and B.-B. Zhang (PSU) report on behalf of the Swift Team: At 09:23:07 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 111212A (trigger=509543). Swift could not slew immediately to the burst due to an observing constraint. The BAT on-board calculated location is RA, Dec 310.404, -68.617 which is RA(J2000) = 20h 41m 37s Dec(J2000) = -68d 37' 01" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a weak emission with a duration of at least 20 sec, but a more detailed description will require the ground-linked data. The peak count rate was ~500 counts/sec (15-350 keV), at ~0 sec after the trigger. Due to an observing constraint, Swift will not slew until T0+47.6 minutes. There will be no XRT or UVOT data until this time. Burst Advocate for this burst is C. A. Swenson (cswenson AT astro.psu.edu). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)