TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4573 SUBJECT: GRB 060117: Suzaku WAM observation of the prompt emission DATE: 06/01/24 17:45:26 GMT FROM: Kazutaka Yamaoka at Aoyama Gakuin U Y.Terada (RIKEN), K.Yamaoka, S.Sugita (Aoyama Gakuin U.), M.Ohno, T.Takahashi, Y.Fukazawa (Hiroshima U.), K.Abe, Y.Endo, S. Hong, K.Onda, M.Tashiro (Saitama U.), G.Sato, K.Nakazawa, T.Takahashi (ISAS/JAXA), R.Miyawaki, M.Kokubun, K.Makishima (Univ. of Tokyo) and the HXD-II team The bright and long burst, GRB 060117 (Swift-BAT trigger #177666; Campana et al., GCN 4533), triggered the Suzaku Wide-band All-sky Monitor (WAM) which is sensitive to an energy band of 50 keV - 5 MeV at 06:50:00 (UT). The observed light curve shows multi-peak structures with a duration (T90) of 16 seconds. The fluence in 100 - 1000 keV was (1.5 +/- 0.1)X10^-5 erg/cm2. The 1-s peak flux was 9.2 +/- 0.4 photons/cm2/s in the same energy range. Preliminary result shows that the time-averaged spectrum is well fitted by a single power law with a photon index of 2.5 +/- 0.2. All the quoted errors are at statistical 90% confidence level. The WAM in-flight calibration is still under way, and systematic errors, such as the flux calibration uncertainties of about 20%, are not included in the errors. The WAM light curve of this event is available at http://www.astro.isas.ac.jp/suzaku/research/HXD-WAM/WAM-GRB/grb/grb_table.html Further detailed analysis and the refinement are in progress.