GCN Circular 15984
Subject
GRB140308A: Suzaku WAM observation of the prompt emission
Date
2014-03-15T08:46:38Z (10 years ago)
From
Makoto Tashiro at Saitama U/Swift <tashiro@phy.saitama-u.ac.jp>
T. Nagayoshi, M. Tashiro, Y. Terada, S. Koyama, T. Yasuda, S. Takeda,
Y.���Ishida, H. Ueno, S. Sugimoto (Saitama U.),
M. Yamauchi, N. Ohmori, M. Akiyama, R. Kinoshita (Univ. of Miyazaki),
M. Ohno, K. Takaki, T. Kawano, R. Nakamura, S. Furui,���Y. Fukazawa
(Hiroshima U.), K. Yamaoka (Nagoya U.), 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 140308A (Konus-Wind detection: S. Golenetskii et al.,
GCN 15943, IPN localization: S. Golenetskii et al., GCN 15941)
was triggered the Suzaku Wide-band All-sky Monitor (WAM)
which covers an energy range of 50 keV - 5 MeV at 03:49:26.030 UT (=T0).
The observed light curve shows a multi-peaked structure starting at
T0-10 s, ending at T0+80 s with a duration (T90) of about 64 seconds.
The fluence in 100 - 1000 keV was 4.02 (-0.78, +0.14) x10^-5 erg/cm^2.
The 1-s peak flux measured from T0+20 s was
7.71 (-5.71, +0.07) photons/cm^2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0-10 s
to T0+80 s is well fitted by a GRB Band model in 90 keV to 5 MeV.
the low-energy photon index alpha: -0.95 (-0.44, +1.11),
the high-energy photon index beta: -2.20 (-0.23, +0.14),
and the peak energy Epeak: 386 (-128, +132) keV
(chi^2/d.o.f = 24.9/25).
Due to the brightness of this burst, a 3% systematic error was added for
low energy channels. All the quoted errors are at statistical 90%
confidence level.
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