Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 24024

MAGIC follow-up of the X-ray flares of LS I +61�303 dete
2019-03-28T17:50:39Z (5 years ago)
Razmik Mirzoyan at MPI/MAGIC <>
R. Mirzoyan, D. Hadasch, A. L�pez-Oramas report on behalf of the MAGIC

The MAGIC telescopes have observed the direction (RA=+02:40:37h,
J2000.0) coincident with the location of the gamma-ray binary LS I +61� 303
DEC:+61:13:45, J2000.0) in the very-high-energy (VHE; >100 GeV) range on
23, 2019. The MAGIC observations were triggered by the flaring activity in
measured by Swift-BAT on March 23, 2019 at 20:30:47 UT (S. D. Barthelmy et
al., GCN
circ. 23989, 2019) and by Swift-XRT at 20:32:12.5 UT. The preliminary
Swift-BAT analysis

showed multiple short spikes with a total duration of about 20 sec and a
peak rate of about 2400

counts/sec (15-350 keV) 3 seconds after the trigger. The analysis of the
data taken ~20 minutes later on March 23, 2019 between 20:52:13.7 UTC (MJD

and 21:12:00.9 UTC (MJD 58565.8833) did not show any significant detection
of LS I +61� 303

at VHE (significance (Li&Ma) < 0.5 sigma). After 0.33 hours of observations
the integral flux

upper limit for energies above 300 GeV is 2e-11 cm^-2 s^-1.

The MAGIC contact persons for these observations are Razmik Mirzoyan
( <>, Daniela
Hadasch ( <>
Alicia L�pez-Oramas ( <>
Looking for U.S. government information and services? Visit