[vsnet-grb-info 5656] GRB 080211: Suzaku WAM observation of the prompt emission

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7315
SUBJECT: GRB 080211: Suzaku WAM observation of the prompt emission 
DATE:    08/02/19 01:00:42 GMT
FROM:    Masanori Ohno at Hiroshima U  <ohno at hirax7.hepl.hiroshima-u.ac.jp>

M. Ohno, T. Uehara, T. Takahashi, Y. Fukazawa, 
C. Kira, Y. Hanabata (Hiroshima U.), 
K. Yamaoka, Y. E. Nakagawa, S. Sugita (Aoyama Gakuin U.), 
M. Tashiro, Y. Terada, Y. Urata, A. Endo,
K. Onda, M. Suzuki, N. Kodaka, K. Morigami (Saitama U.), 
T. Tamagawa (RIKEN),
T. Enoto, R. Miyawaki, K. Nakazawa, K. Makishima (Univ. of Tokyo),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki),
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), 
S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The bright, long, IPN localized GRB 080211 (Hurley et al., GCN 7295)
was detected by the the Suzaku Wide-band  All-sky Monitor (WAM) which
covers an energy range of 50 keV - 5 MeV at 07:23:39 UT (=T0).
The observed light curve shows a multi-peaked structure, starting at
T0-10 s, ending at T0+25 s with a duration (T90) of about 25 seconds.
The fluence in 100 - 1000 keV was 2.8(+0.1,-0.1) x 10^-5 erg/cm^2.
The 1-s peak flux measured from T0+6 s was 5.5(+0.4,-0.6)
photons/cm^2/s in the same  energy range.

Preliminary result shows that the time-averaged spectrum from
T0-10s to T0+25s is well fitted by a power-law with exponential cutoff
model:
 dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
 alpha       1.1(+0.2,-0.2), and
 Epeak       483(+66,-46) keV (chi^2/d.o.f. = 38/21).

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 will be
appeared at:

 http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html