Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published April 2012 | Published + Supplemental Material
Journal Article Open

The origin of the early-time optical emission of Swift GRB 080310

Abstract

We present broad-band multiwavelength observations of GRB 080310 at redshift z= 2.43. This burst was bright and long-lived, and unusual in having extensive optical and near-infrared (IR) follow-up during the prompt phase. Using these data we attempt to simultaneously model the gamma-ray, X-ray, optical and IR emission using a series of prompt pulses and an afterglow component. Initial attempts to extrapolate the high-energy model directly to lower energies for each pulse reveal that a spectral break is required between the optical regime and 0.3 keV to avoid overpredicting the optical flux. We demonstrate that afterglow emission alone is insufficient to describe all morphology seen in the optical and IR data. Allowing the prompt component to dominate the early-time optical and IR and permitting each pulse to have an independent low-energy spectral indices we produce an alternative scenario which better describes the optical light curve. This, however, does not describe the spectral shape of GRB 080310 at early times. The fit statistics for the prompt- and afterglow-dominated models are nearly identical making it difficult to favour either. However one enduring result is that both models require a low-energy spectral index consistent with self-absorption for at least some of the pulses identified in the high-energy emission model.

Additional Information

© 2012 The Authors. Monthly Notices of the Royal Astronomical Society © 2012 RAS. Accepted 2012 January 5. Received 2012 January 5; in original form 2011 September 12. Article first published online: 29 Feb 2012. Based on observations made also with ESO telescopes at the La Silla and Paranal Observatory under programme IDs 080.D-0250 and 080.D-0791. We would like to thank the referee for their useful comments. This work is supported at the University of Leicester by the STFC. AVF and WL acknowledge generous financial assistance from NASA/Swift grants NNX10AI21G and GO-7100028, the TABASGO Foundation, and US National Science Foundation (NSF) grant AST-0908886. KAIT and its ongoing operation were made possible by donations from Sun Microsystems, Inc., the Hewlett-Packard Company, AutoScope Corporation, Lick Observatory, the NSF, the University of California, the Sylvia & Jim Katzman Foundation, and the TABASGO Foundation.

Attached Files

Published - Littlejohns2012p18074Mon_Not_R_Astron_Soc.pdf

Supplemental Material - MNR_20499_sm_TablesA1toA8.zip

Files

MNR_20499_sm_TablesA1toA8.zip
Files (2.7 MB)
Name Size Download all
md5:438845d02982a65cdcd496ad19c9636c
47.8 kB Preview Download
md5:ac429a9a83489f753edd2c41d09d62e6
2.6 MB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 17, 2023