TITLE: GCN CIRCULAR NUMBER: 6808 SUBJECT: GRB 070920B: Swift detection of a burst DATE: 07/09/20 21:13:46 GMT FROM: Scott Barthelmy at NASA/GSFC J. L. Racusin (PSU), S. D. Barthelmy (GSFC), J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/GSFC/USRA), H. A. Krimm (GSFC/USRA), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), C. Pagani (PSU), D. M. Palmer (LANL), M. Stamatikos (NASA/ORAU), T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the Swift Team: At 21:04:32 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 070920B (trigger=291728). The BAT on-board calculated location is RA, Dec 0.144, -34.819 which is RA(J2000) = 00h 00m 35s Dec(J2000) = -34d 49' 06" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single peak with a duration of about 35 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger. Because Swift is in the process of returning to normal operations, automatic slewing to GRBs is currently disabled. Therefore, there are no prompt XRT or UVOT observations of this burst. Burst Advocate for this burst is J. L. Racusin (racusin 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.)