[vsnet-grb-info 9262] GRB 100510A: Fermi GBM detection/observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10745
SUBJECT: GRB 100510A: Fermi GBM detection/observation
DATE:    10/05/12 18:52:10 GMT
FROM:    Narayana Bhat at U Alabama/Huntsville/GBM  <Narayana.Bhat at nasa.gov>

P. N. Bhat (UAH), Vandiver Chaplin (UAH), Valerie Connaughton (UAH)
and Chip Meegan (USRA)
report on behalf of the Fermi GBM Team:

"At 19:27:06.97 UT on 10 May 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100510 (trigger 295212428 / 100510810),
which was also detected by the MAXI/GSC (Morii et al. 2010, GCN 10739)

The on-ground calculated location, using the GBM trigger
data, is RA = 355.05, DEC = -18.86 (J2000 degrees,
equivalent to 23 h 40 m, -18 d 52 '), with an uncertainty
of 5 degrees (radius, 1-sigma containment,
statistical only; The GBM on-ground location is subject to systematic
errors due to blockage by the solar panels at this orientation.)
 
The angle from the Fermi LAT boresight is 90 degrees.

The GBM light curve consists of a single FRED
with a duration (T90) of about 31 s (50-300 keV).
The time-averaged spectrum from T0-11 s to T0+54 s is
adequately fit by a power law function with an exponential
high energy cutoff.  The power law index is -0.97 +/- 0.18 and
the cutoff energy, parameterized as Epeak, is 70 +/- 6.8 keV

(C-stat value 553.2 for 242 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(2.68 +/- 0.08)E-06 erg/cm^2. The 0.256-sec peak photon flux measured
starting from T0 s in the 8-1000 keV band
is 0.8 +/- 0.03 ph/s/cm^2.

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