Observations of the Prompt Gamma‐Ray Emission of GRB 070125

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 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" 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 × 10 52 ergs, is the largest yet observed. © 2008. The American Astronomical Sociely. All rights reserved.