TITLE: GCN CIRCULAR NUMBER: 9122 SUBJECT: GRB 090410: Swift detection of a burst DATE: 09/04/10 17:10:20 GMT FROM: David Palmer at LANL D. Grupe (PSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (MSSL), K. L. Page (U Leicester), D. M. Palmer (LANL), J. L. Racusin (PSU), M. H. Siegel (PSU), M. Stamatikos (NASA/ORAU), M. C. Stroh (PSU) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At 16:57:52 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090410 (trigger=348929). Swift could not slew to the GRB due to a Sun constraint. The BAT on-board calculated location is RA, Dec 334.980, +15.471 which is RA(J2000) = 22h 19m 55s Dec(J2000) = +15d 28' 16" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex peak from T-10 to T+40, followed by another broad peak from T+80 to T+140. The peak count rate was ~6000 counts/sec (15-350 keV), at ~6 sec after the trigger. Swift cannot slew to the BAT position. The burst is sun-constrained until Tuesday, 2009 April 14. There will thus be no XRT or UVOT data for this trigger. Burst Advocate for this burst is D. Grupe (grupe 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.)