[vsnet-grb-info 13039] GRB 130408A: Suzaku WAM observation of the prompt emission

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14376
SUBJECT: GRB 130408A: Suzaku WAM observation of the prompt emission
DATE:    13/04/15 20:47:15 GMT
FROM:    Masanori Ohno at Hiroshima U  <ohno at hep01.hepl.hiroshima-u.ac.jp>

K. Takaki, M. Ohno, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa
(Hiroshima U.),
M. Tashiro, Y. Terada, T. Yasuda, Y. Ishida, H. Ueno, S. Sugimoto(Saitama
U.),
K. Yamaoka (Nagoya U.), M. Yamauchi, M. Akiyama, N. Ohmori (Univ. of
Miyazaki),
S. Sugita (Ehime U.), Y. E. Nakagawa, M. Kokubun,
T. Takahashi (ISAS/JAXA), W. Iwakiri(RIKEN), Y. Hanabata (ICRR), Y. Urata
(NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo) on behalf of the Suzaku
WAM team, report:

The long GRB 130408A (Lien et al., GCN14361) triggered by the
Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of
50 keV - 5 MeV at 21:51:38 UT (=T0).

The observed light curve shows a single peak starting at T0-2s, ending
at T0+5s with a duration (T90) of about 7 seconds.
The fluence in 100 - 1000 keV was 7.18(+0.06/-0.15) x 10^-6 erg/cm^2.
The 1-s peak flux measured from T0s was 5.42(+1.37/-2.27) photons/cm^2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0-2s to
T0+5s is well fitted by a single power-law with a photon index of
2.32 (+0.41/-0.34) (chi2/d.o.f = 12.19/13).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst will be available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html