The CALET Gamma-ray Burst Monitor (CGBM)

Kazutaka Yamaoka; Atsumasa Yoshida; Takanori Sakamoto; Ichiro Takahashi; Takumi Hara; Tatsuma Yamamoto; Yuta Kawakubo; Ry ota Inoue; Shunsuke Terazawa; Rie Fujioka; Kazumasa Senuma; Satoshi Nakahira; Hiroshi Tomida; Shiro Ueno; Shoji Torii; Michael L. Cherry; Sergio Ricciarini; the CALET collaboration

arXiv · 1311.4084

The CALET Gamma-ray Burst Monitor (CGBM)

Kazutaka Yamaoka·Atsumasa Yoshida·Takanori Sakamoto·Ichiro Takahashi·Takumi Hara·Tatsuma Yamamoto·Yuta Kawakubo·Ry ota Inoue·Shunsuke Terazawa·Rie Fujioka·Kazumasa Senuma·Satoshi Nakahira·Hiroshi Tomida·Shiro Ueno·Shoji Torii·Michael L. Cherry·Sergio Ricciarini·the CALET collaboration

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Abstract

The CALET Gamma-ray Burst Monitor (CGBM) is the secondary scientific instrument of the CALET mission on the International Space Station (ISS), which is scheduled for launch by H-IIB/HTV in 2014. The CGBM provides a broadband energy coverage from 7 keV to 20 MeV, and simultaneous observations with the primary instrument Calorimeter (CAL) in the GeV - TeV gamma-ray range and Advanced Star Camera (ASC) in the optical for gamma-ray bursts (GRBs) and other X-gamma-ray transients. The CGBM consists of two kinds of scintillators: two LaBr$_3$(Ce) (7 keV - 1 MeV) and one BGO (100 keV - 20 MeV) each read by a single photomultiplier. The LaBr$_3$(Ce) crystal, used in space for the first time here for celestial gamma-ray observations, enables GRB observations over a broad energy range from low energy X-ray emissions to gamma rays. The detector performance and structures have been verified using the bread-board model (BBM) via vibration and thermal vacuum tests. The CALET is currently in the development phase of the proto-flight model (PFM) and the pre-flight calibration of the CGBM is planned for August 2013. In this paper, we report on the current status and expected performance of CALET for GRB observations.

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Kazutaka Yamaoka, Atsumasa Yoshida, Takanori Sakamoto, Ichiro Takahashi, Takumi Hara, Tatsuma Yamamoto, Yuta Kawakubo, Ry ota Inoue, Shunsuke Terazawa, Rie Fujioka, Kazumasa Senuma, Satoshi Nakahira, Hiroshi Tomida, Shiro Ueno, Shoji Torii, Michael L. Cherry, Sergio Ricciarini, the CALET collaboration. 2013-11-16. The CALET Gamma-ray Burst Monitor (CGBM). https://arxiv.org/abs/1311.4084

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