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 22960

GRB 180718A: Fermi GBM detection
2018-07-19T03:53:43Z (6 years ago)
Rachel Hamburg at UAH <>
R. Hamburg (UAH), P. Veres (UAH), and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 01:57:44.60 UT on 18 July 2018, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 180718A (trigger 553571869 / 180718082),
which was also detected by the INTEGRAL SPI-ACS and subsequently
localized by IPN. Ground analysis of the Swift/BAT data revealed
a detection consistent with the IPN annulus (GCN 22959).

The angle from the Fermi LAT boresight at the GBM trigger time is 61

The GBM light curve consists of a single peak
with a duration (T90) of about 0.08 s (50-300 keV).
The time-averaged spectrum from T0-0.06 s to T0+0.02 s is
adequately fit by a Band function with Epeak = 187 +/- 61 keV,
alpha = -0.2 +/- 0.4, and beta = -2.3 +/- 0.5.

The event fluence (10-1000 keV) in this time interval is
(2.3 +/- 0.3)E-07 erg/cm^2. The 64-ms peak photon flux measured
starting from T0-0.05 s in the 10-1000 keV band
is 9 +/- 1 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
Looking for U.S. government information and services? Visit