{
  "bibcode": "2019GCN.24913....1K",
  "body": "H. A. Krimm (NSF), N. J. Klingler (PSU), K. L. Page (U Leicester) and\nA. Tohuvavohu (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 06:02:08 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated possible GRB 190630B (trigger=912102).  Swift slewed immediately to the location. \nThe BAT on-board calculated location is \nRA, Dec 223.669, +41.521 which is \n   RA(J2000) = 14h 54m 41s\n   Dec(J2000) = +41d 31' 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 5 sec.  The peak count rate\nwas ~1000 counts/sec (15-350 keV), at ~0 sec after the trigger. \nThis increase in flux occurred during a rise in background due to\nentry to the SAA, so it is not immediately clear from the BAT data \nalone that this is indeed a burst rather than a noise event. \n\nThe XRT began observing the field at 06:03:10.7 UT, 62.1 seconds after\nthe BAT trigger. No source was detected in the 2.5-s promptly available\nimage. We are waiting for the full dataset to detect and localise the\nXRT counterpart. \n\nUVOT took a finding chart exposure of  66 seconds with the White filter\nstarting 65 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 25% of\nthe BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nBAT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.01. \n\nDue to the high background in the BAT and the lack of immediate\ncounterpart detection in the XRT, the Swift team will not be able to\nconfirm or deny whether this event is a GRB without further data. \n\nBurst Advocate for this burst is H. A. Krimm (hkrimm AT nsf.gov). \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": 24913,
  "createdOn": 1561875887000,
  "email": "hkrimm@nsf.gov",
  "subject": "Swift Trigger 912102:  possible GRB 190630B",
  "submitter": "Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>",
  "eventId": "GRB 190630B"
}