TITLE: GCN CIRCULAR NUMBER: 15460 SUBJECT: GRB 131029A: Suzaku WAM observation of the prompt emission DATE: 13/11/06 03:23:09 GMT FROM: Makoto Tashiro at Saitama U/Swift H. Ueno, M. Tashiro, Y. Terada, T. Yasuda, Y. Ishida, S. Sugimoto (Saitama U.), M. Ohno, K. Takaki, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa (Hiroshima U.), M. Yamauchi, N. Ohmori, M. Akiyama, R. Kinoshita (Univ. of Miyazaki), 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 131029A (Fermi-LAT detection: A. von Kienlin, et al., GCN 15401) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at UT 23:20:48.884 (=T0). The observed light curve shows a two-peaked structure starting at T0-5.0 s, ending at T0+110 s with a duration (T90) of about 84 seconds. The fluence in 100 - 1000 keV was 1.51 (-0.36, +0.24) *10^-5 erg/cm^2. The 1-s peak flux measured from T0+4.0 s was 1.55 (-0.92, +1.3) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0-2 s to T0+110 s is well fitted by a single power-law with a photon index of 1.87 (-0.17, +0.17) (chi2/d.o.f = 12.4/12). 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