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GCN Circular 10397

GRB 100205B: Fermi GBM detection
2010-02-07T18:20:33Z (14 years ago)
David Gruber at MPE <>
David Gruber (MPE)
reports on behalf of the Fermi GBM Team:

"At 11:45:38.26 UT on 05 February 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100205B (trigger 287063140 / 100205490).

The on-ground calculated location, using the GBM trigger
data, is RA = 133.9, DEC = -23.0 (J2000 degrees,
equivalent to 08h 55m, 23d 00'), with an uncertainty
of 8.2 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 102 degrees.

The GBM light curve consists of a single pulse
with a duration (T90) of about 13.6 +/- 1.6s (8-1000 keV).
The time-averaged spectrum from T0-1.024s to T0+7.168 s is
best fit by a power law function with an exponential
high energy cutoff. The power law index is -0.47 (+0.20/-0.19) and
the cutoff energy, parameterized as Epeak, is 124.20 (+16.0/-12.2)keV
(c-stat 468.61 for 349 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(1.410 +/-  0.082)E-6 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0 in the 8-1000 keV band
is 2.98 +/- 0.22 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
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