{
  "bibcode": "2014GCN.16202....1S",
  "body": "C. A. Swenson (PSU), S. D. Barthelmy (GSFC), M. M. Chester (PSU) and\nP. A. Evans (U Leicester) report on behalf of the Swift Team:\n\nAt 08:30:20 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 140502A (trigger=597841).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 319.155, +49.018 which is \n   RA(J2000)  =  21h 16m 37s\n   Dec(J2000) = +49d 01' 04\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve shows a single peak\nwith a duration of about 25 sec.  The peak count rate\nwas ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 08:31:31.3 UT, 70.8 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source located at RA, Dec 319.18744, 48.97012 which is equivalent\nto:\n   RA(J2000)  = 21h 16m 44.99s\n   Dec(J2000) = +48d 58' 12.4\"\nwith an uncertainty of 4.0 arcseconds (radius, 90% containment). This\nlocation is 188 arcseconds from the BAT onboard position, outside the\nBAT error circle. This position may be improved as more data are\nreceived; the latest position is available at\nhttp://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density consistent with the Galactic value of 9.47\nx 10^21 cm^-2 (Willingale et al. 2013). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 74 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers none of\nthe XRT error circle. The 8'x8' region for the list of sources generated\non-board covers 100% of the XRT error circle. The list of sources is typically\ncomplete to about 18 mag. No correction has been made for the large, but\nuncertain extinction expected. \n\nBurst Advocate for this burst is C. A. Swenson (cswenson AT astro.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/too.html.)",
  "circularId": 16202,
  "createdOn": 1399020240000,
  "email": "scott@milkyway.gsfc.nasa.gov",
  "subject": "GRB 140502A: Swift detection of a burst",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>",
  "eventId": "GRB 140502A"
}