TITLE: GCN CIRCULAR NUMBER: 15748 SUBJECT: GRB 140118A: Swift detection of a burst DATE: 14/01/18 01:40:21 GMT FROM: David Palmer at LANL H. A. Krimm (CRESST/GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. A. Kennea (PSU), V. Mangano (PSU), C. B. Markwardt (NASA/GSFC), C. Pagani (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team: At 01:32:02 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 140118A (trigger=584136). Swift did not slew to the burst because the location is sun-constrained. The BAT on-board calculated location is RA, Dec 331.003, -17.948 which is RA(J2000) = 22h 04m 01s Dec(J2000) = -17d 56' 50" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a broad triangle- shaped peak structure with a duration of about 40 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~3 sec after the trigger. Due to a Sun observing constraint, Swift cannot slew to the BAT position until 07:34 UT on 2014 April 03. There will thus be no XRT or UVOT data for this trigger before this time. Burst Advocate for this burst is H. A. Krimm (hans.krimm AT nasa.gov). 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.)