//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31374 SUBJECT: Alert from the HAWC Burst Monitor HAWC-220103A DATE: 22/01/03 15:47:08 GMT FROM: Hugo Ayala at Pennsylvania State University The HAWC Collaboration (http://www.hawc-observatory.org/collaboration/) reports: On 01 03, 2022, at 08:01:56 UT, HAWC detected a burst signal from its Burst Monitoring named HAWC-220103A. This monitor system looks for excesses above the expected background in time windows of 0.2, 1, 10 and 100 seconds. This event was found in the 10-second time window starting at the reported trigger time. The position of the alert is RA (J200): 156.33 deg Dec (J2000): 1.83 deg Location uncertainty (68% containment): 0.60 deg (statistical only). The monitor system found that this alert has a false alarm rate of 5.63 alert(s) per year. We encourage follow-up observations of the HAWC alert region. We however note that it is consistent with background expectation based on the observation time. The initial automated alert is recorded in here: https://gcn.gsfc.nasa.gov/notices_amon_hawc/1010460_557.amon HAWC is a very-high-energy gamma-ray observatory operating in Central Mexico at latitude 19 deg. north. Operating day and night with over 95% duty cycle, HAWC has an instantaneous field of view of 2 sr and surveys 2/3 of the sky every day. It is sensitive to gamma rays from 300 GeV to 100 TeV.