Observations of the Prompt Gamma-Ray Emission of GRB 070125

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 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 multipeaked emission over a period of about 1 minute. The total burst fluence as observed by Konus is -->1.79 ? 10?4 ergs cm?2 (20 keV-10 MeV). Using the spectroscopic redshift -->z = 1.548, we find that the burst is consistent with the Amati -->Epeak,i ? Eiso correlation. Assuming a jet opening angle derived from broadband modeling of the burst afterglow, GRB 070125 is a significant outlier to the Ghirlanda -->Epeak,i ? E? correlation. Its collimation-corrected energy release, -->E? = 2.5 ? 1052 ergs, is the largest yet observed.

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