{
  "submittedHow": "email",
  "createdOn": 1790321699825,
  "subject": "GRB 260925A: Swift detection of a burst",
  "body": "E. Ambrosi (INAF-IASFPA), S. Dichiara (PSU), A. Melandri (INAF-OAR),\nK. L. Page (U Leicester), B. Sbarufatti (INAF-OAB) and\nM. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 07:13:02 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 260925A (trigger=1513316).  Swift slewed immediately to the burst.\nThe BAT on-board calculated location is \nRA, Dec 132.462, +24.971,  which is \n   RA(J2000) = 08h 49m 51s\n   Dec(J2000) = +24d 58' 16\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a single-peaked\nstructure with a duration of about 15 sec.  The peak count rate\nwas ~1200 counts/sec (15-350 keV), at ~1 sec after the trigger.\n\nThe XRT began observing the field at 07:14:52.2 UT, 110.7 seconds after\nthe BAT trigger. Using promptly downlinked data we find a fading,\nuncatalogued X-ray source with an enhanced position: RA, Dec 132.45674,\n24.91182 which is equivalent to:\n   RA(J2000)  = 08h 49m 49.62s\n   Dec(J2000) = +24d 54' 42.6\"\nwith an uncertainty of 2.3 arcseconds (radius, 90% containment). This\nlocation is 213 arcseconds from the BAT onboard position. This position\nmay be improved as more data are received; the latest position is\navailable at https://www.swift.ac.uk/sper. This position is more than\n2-sigma away from the BAT position, and so possibly unrelated to the\ntrigger. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density consistent with the Galactic value of 3.64\nx 10^20 cm^-2 (Willingale et al. 2013).\n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 119 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 expected\nextinction corresponding to E(B-V) of 0.038.\n\nBurst Advocate for this burst is E. Ambrosi (elena.ambrosi AT inaf.it).\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/)\n\n",
  "submitter": "Jimmy DeLaunay at PSU <jjd330@psu.edu>",
  "eventId": "GRB 260925A",
  "circularId": 45739
}