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arXiv · 0710.4590

Observations of the Prompt Gamma-Ray Emission of GRB 070125

Eric C. Bellm·Kevin Hurley·Valentin Pal'shin·Kazutaka Yamaoka·Mark S. Bandstra·Steven E. Boggs·Soojing Hong·Natsuki Kodaka·A. S. Kozyrev·M. L. Litvak·I. G. Mitrofanov·Yujin E. Nakagawa·Masanori Ohno·Kaori Onda·A. B. Sanin·Satoshi Sugita·Makoto Tashiro·V. I. Tretyakov·Yuji Urata·Claudia Wigger
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Abstract

The long, bright gamma-ray burst GRB 070125 was localized by the Interplanetary Network. We present light curves of the prompt gamma-ray emission as observed by Konus-WIND, RHESSI, Suzaku-WAM, and \textit{Swift}-BAT. We detail the results of joint spectral fits with Konus and RHESSI data. The burst shows moderate hard-to-soft evolution in its multi-peaked emission over a period of about one minute. The total burst fluence as observed by Konus is $1.79 \times 10^{-4}$ erg/cm$^2$ (20 keV--10 MeV). Using the spectroscopic redshift $z=1.548$, we find that the burst is consistent with the ``Amati'' $E_{peak,i}-E_{iso}$ correlation. Assuming a jet opening angle derived from broadband modeling of the burst afterglow, GRB 070125 is a significant outlier to the ``Ghirlanda'' $E_{peak,i}-E_γ$ correlation. Its collimation-corrected energy release $E_γ= 2.5 \times 10^{52}$ ergs is the largest yet observed.

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Eric C. Bellm, Kevin Hurley, Valentin Pal'shin, Kazutaka Yamaoka, Mark S. Bandstra, Steven E. Boggs, Soojing Hong, Natsuki Kodaka, A. S. Kozyrev, M. L. Litvak, I. G. Mitrofanov, Yujin E. Nakagawa, Masanori Ohno, Kaori Onda, A. B. Sanin, Satoshi Sugita, Makoto Tashiro, V. I. Tretyakov, Yuji Urata, Claudia Wigger. 2008-07-28. Observations of the Prompt Gamma-Ray Emission of GRB 070125. https://doi.org/10.1086/592136

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