{
  "bibcode": "2021GCN.30413....1S",
  "body": "B. Sbarufatti (PSU), H. A. Krimm (NSF), S. Laha (GSFC/UMBC/CRESST),\nA. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC),\nD. M. Palmer (LANL), M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 02:25:37 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 210708A (trigger=1059460).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 173.699, -49.187 which is \n   RA(J2000) = 11h 34m 48s\n   Dec(J2000) = -49d 11' 11\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a complex\nstructure with a duration of about 10 sec.  The peak count rate\nwas ~1300 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 02:26:37.5 UT, 60.5 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source located at RA, Dec 173.73706, -49.15179 which is\nequivalent to:\n   RA(J2000)  = 11h 34m 56.89s\n   Dec(J2000) = -49d 09' 06.4\"\nwith an uncertainty of 12.2 arcseconds (radius, 90% containment). This\nposition may be improved as more data are received; the latest position\nis available at https://www.swift.ac.uk/sper.  We cannot determine\nwhether the source is fading at the present time. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (1.58 x\n10^21 cm^-2, Willingale et al. 2013), with an excess column of 3.5\n(+3.01/-2.55) x 10^21 cm^-2 (90% confidence). \n\nUVOT data is not immediately available, possibly due to a bright\nstar (mag=5.5) within 1 arcminute of the XRT location. \n\nBurst Advocate for this burst is B. Sbarufatti (bxs60 AT psu.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)",
  "circularId": 30413,
  "createdOn": 1625712032000,
  "email": "palmer@lanl.gov",
  "subject": "GRB 210708A: Swift detection of a burst",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>",
  "eventId": "GRB 210708A"
}