GCN Circular 7624
Subject
GRB 080413A: Suzaku WAM observation of the prompt emission
Date
2008-04-16T16:11:23Z (17 years ago)
From
Kazutaka Yamaoka at Aoyama Gakuin U <yamaoka@phys.aoyama.ac.jp>
T. Enoto (Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN),
T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata
(Hiroshima U.), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), M. Tashiro,
Y. Terada, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami (Saitama U.),
K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi,
H. Tanaka, R. Hara (Univ. of Miyazaki), M. Ohno, M. Kokubun,
M. Suzuki, T. Takahashi (ISAS/JAXA), S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:
The long GRB 080413A (Swift/BAT trigger #309096 ; Beardmore et al., GCN
7594) was detected by the Suzaku Wide-band All-sky Monitor (WAM)
which covers an energy range of 50 keV - 5 MeV at 02:54:18.648 UT (=T0).
The observed light curve shows a clear double-peaked structure
at T0+2s and T0+16s, and possible weak peak at T0+45s,
with a total duration (T90) of about 19 seconds.
The fluence in 150 - 1000 keV was (2.2 +/- 0.5) x 10^-6 erg/cm^2.
The 1-s peak flux measured from T0+2s was 0.77 +/- 0.19 photons/cm^2/s
in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0+0s to T0+20s
is fitted by a single power-law with a photon index of
2.4 +/- 0.4 (chi^2/d.o.f = 15.1/10) in 150 - 1000 keV.
All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.
The light curves with 1-sec time resolution for this burst are now available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html