The wide-band all-sky monitor (WAM) is the secondary function of large lateral BGO shield of the Hard X-ray Detector (HXD) onboard the Suzaku mission. Owing to its large geometrical area of 800 cm2 per side and wide-field of view, the WAM is very suitable to observe gamma-ray bursts (GRBs) in the energy range of 50--5000 keV. It has actually observed 183 GRBs confirmed by other satellites since the Suzaku launch. In this paper, we present recent results such as spectral properties of short hard GRBs, peak-energy distributions, updated Amati-relation, time variablity in the MeV gammma-ray range, and distribution of the T90 duration, obtained from the WAM observations over initial two years.

Suzaku HXD-WAM collaboration

Proceedings of the 30th International Cosmic Ray Conference; Rogelio Caballero, Juan Carlos D'Olivo, Gustavo Medina-Tanco, Lukas Nellen, Federico A. Sánchez, José F. Valdés-Galicia (eds.); Universidad Nacional Autónoma de México, Mexico City, Mexico, 2008; Vol. 3 (OG part 2), pages 1151-1154