[vsnet-grb-info 3709] GRB 060904A: Suzaku/WAM observation of the prompt emission

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5543
SUBJECT: GRB 060904A: Suzaku/WAM observation of the prompt emission
DATE:    06/09/08 04:47:19 GMT
FROM:    Makoto Tashiro at Saitama U/Swift  <tashiro at phy.saitama-u.ac.jp>

  M. Tashiro, K. Abe, K. Onda, Y. Sato, M. Suzuki, Y. Urata (Saitama U.),
  M. Ohno, T. Takahashi, T. Asano, T. Uehara, Y. Fukazawa (Hiroshima U.),
  K. Yamaoka, S. Sugita (Aoyama Gakuin U.), T. Enoto, R. Miyawaki,
  K. Kokubun, K. Makishima (Univ. of Tokyo), K. Nakazawa, T. Takahashi
  (ISAS/JAXA),   M. Suzuki, Y. Terada, T. Tamagawa (RIKEN),
  S. Hong (Nihon U.), on behalf of the Suzaku WAM team report:

  The bright, long burst, GRB 060904A (Swift-BAT trigger #227996;
  D. Grupe et al., GCN 5502; Krimm et al., GCN 5516), triggered
  the Suzaku Wideband All-sky Monitor (WAM) which covers an energy
  range of 50 keV - 5 MeV at 01:04:09.040 (UT).
  The three little peaks and following large peak (GCN 5502) are
  clearly seen in the light curve observed with the WAM.
  The T90 duration was ~79 seconds.
  The fluence in 100 - 1000 keV was 8.66(-4.19 +0.39)x10-6 erg/cm2,
  while the 1-s peak flux was 2.07(-1.12 +0.09) photons/cm2/s in the
   same energy range.

  Preliminary result shows that the time-averaged spectrum is
  well described with a single power-law model with the energy index
  of 1.16 (-0.18 0.20).

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