TITLE: GCN CIRCULAR NUMBER: 17193 SUBJECT: GRB 141207A: Suzaku WAM observation of the prompt emission DATE: 14/12/19 04:58:51 GMT FROM: Makoto Tashiro at Saitama U/Swift T. Fujinuma, M. Tashiro, Y. Terada, T. Yasuda, S. Koyama, S. Takeda, T. Nagayoshi, J. Enomoto, S. Nakaya, S. Matsuoka (Saitama U.), M. Yamauchi, N. Ohmori, R. Kinoshita (Univ. of Miyazaki), W. Iwakiri (RIKEN), K. Yamaoka (Nagoya U.), S. Sugita (Ehime U.), Y. Hanabata (ICRR), M. Ohno, T. Kawano, S. Furui, Y. Fukazawa (Hiroshima U.), Y. E. Nakagawa, M. Kokubun, T. Takahashi (ISAS/JAXA), Y. Urata (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo) on behalf of the Suzaku WAM team, report: The long GRB 141207A(Fermi-LAT Detection: Kocevski et al.,GCN 17146; Swift-XRT observation:Amaral-Rogers et al.,GCN 17149;Fermi GBM dection: Burns et al.,GCN 17150) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 19:11:22.452 UT (=T0). The observed light curve shows a multi-peaked structure starting at T0-1s, ending at T0+22s with a duration(T90) of about 20 seconds. The fluence in 100 - 1000 keV was 1.94(+0.10/-0.19)x10^-5 erg/cm^2.The 1-s peak flux measured from T0+6s was 4.74(+0.37/-1.32) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0-1s to T0+22s is well fitted by a power-law with exponential cutoff model: dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with alpha 1.11(+0.40/-0.48), and Epeak 579(+126/-92) keV (chi^2/d.o.f. = 28.2/25). Due to the brightness of this burst, a 3% systematic error was added for low energy channels. There might be uncertainty since the response for the incident angle of GRB photons to WAM is not reliable. 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