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GCN Circular 31374

Alert from the HAWC Burst Monitor HAWC-220103A
2022-01-03T15:47:08Z (2 years ago)
Hugo Ayala at Pennsylvania State University <>
The HAWC Collaboration  (

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:

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.
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