TITLE: GCN CIRCULAR NUMBER: 11581 SUBJECT: GRB 110119A: Swift detection of a burst with an optical detection DATE: 11/01/19 22:31:42 GMT FROM: Scott Barthelmy at NASA/GSFC E. Troja (NASA/GSFC/ORAU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), M. M. Chester (PSU), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), N. P. M. Kuin (UCL-MSSL), C. B. Markwardt (NASA/GSFC), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), T. Sakamoto (NASA/UMBC), B. Sbarufatti (INAF-OAB/IASFPA), M. H. Siegel (PSU), R. L. C. Starling (U Leicester) and G. Stratta (ASDC) report on behalf of the Swift Team: At 22:20:58 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 110119A (trigger=442978). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 348.558, +5.985 which is RA(J2000) = 23h 14m 14s Dec(J2000) = +05d 59' 05" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 95 sec. The peak count rate was ~4500 counts/sec (15-350 keV), at ~35 sec after the trigger. The XRT began observing the field at 22:21:56.0 UT, 57.6 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 348.5881, +5.9874 which is equivalent to: RA(J2000) = 23h 14m 21.14s Dec(J2000) = +05d 59' 14.6" with an uncertainty of 6.2 arcseconds (radius, 90% containment). This location is 108 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy. UVOT took a finding chart exposure of 150 seconds with the White filter starting 67 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 23:14:20.61 = 348.58587 DEC(J2000) = +05:59:10.5 = 5.98626 with a 90%-confidence error radius of about 0.61 arc sec. This position is 9.0 arc sec. from the center of the XRT error circle. The estimated magnitude is 16.48 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.12. Burst Advocate for this burst is E. Troja (eleonora.troja 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.)