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arXiv · 1507.03772

Soft X-ray Observation of the Prompt Emission of GRB100418A

Ritsuko Imatani·Hiroshi Tomida·Satoshi Nakahira·Masashi Kimura·Takanori Sakamoto·Makoto Arimoto·Yoshitaka Morooka·Daisuke Yonetoku·Nobuyuki Kawai·Hiroshi Tsunemi
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Abstract

We have observed the prompt emission of GRB100418A, from its beginning by the MAXI/SSC (0.7-7 keV) on board the International Space Station followed by the Swift/XRT (0.3-10 keV) observation. The light curve can be fitted by a combination of a power law component and an exponential component (decay constant is $31.6\pm 1.6$ sec). The X-ray spectrum is well expressed by the Band function with $E_{\rm p}\leq$8.3 keV. This is the brightest GRB showing a very low value of $E_{\rm p}$. It satisfies the Yonetoku-relation ($E_{\rm p}$-$L_{\rm p}$). It is also consistent with the Amati relation ($E_{\rm p}$-$E_{\rm iso}$) in 2.5$σ$ level.

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Ritsuko Imatani, Hiroshi Tomida, Satoshi Nakahira, Masashi Kimura, Takanori Sakamoto, Makoto Arimoto, Yoshitaka Morooka, Daisuke Yonetoku, Nobuyuki Kawai, Hiroshi Tsunemi. 2015-07-29. Soft X-ray Observation of the Prompt Emission of GRB100418A. https://doi.org/10.1093/pasj%2Fpsv075

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