GRB 081203A: Swift UVOT captures the earliest ultraviolet spectrum of a gamma-ray burst Academic Article uri icon

abstract

  • Abstract We present the earliest ultraviolet (UV) spectrum of a gamma-ray burst (GRB) as observed with the Swift Ultra-Violet/Optical Telescope (UVOT). The GRB 081203A spectrum was observed for 50 s with the UV-grism starting 251 s after the Swift-Burst-Alert-Telescope (BAT) trigger. During this time, the GRB was 13.4 mag (u filter) and was still rising to its peak optical brightness. In the UV-grism spectrum, we find a damped Ly line, Ly and the Lyman continuum break at a redshift z= 2.05 0.01. A model fit to the Lyman absorption implies a gas column density of log NH i= 22.0 0.1 cm2, which is typical of GRB host galaxies with damped Ly absorbers. This observation of GRB 081203A demonstrates that for brighter GRBs (v 14 mag) with moderate redshift (0.5 > z > 3.5) the UVOT is able to provide redshifts, and probe for damped Ly absorbers within 46 min from the time of the Swift-BAT trigger.

published proceedings

  • Monthly Notices of the Royal Astronomical Society: Letters

author list (cited authors)

  • Kuin, N., Landsman, W., Page, M. J., Schady, P., Still, M., Breeveld, A. A., ... Smith, P. J.

citation count

  • 32

complete list of authors

  • Kuin, NPM||Landsman, W||Page, MJ||Schady, P||Still, M||Breeveld, AA||De Pasquale, M||Roming, PWA||Brown, PJ||Carter, M||James, C||Curran, PA||Cucchiara, A||Gronwall, C||Holland, ST||Hoversten, EA||Hunsberger, S||Kennedy, T||Koch, S||Lamoureux, H||Marshall, FE||Oates, SR||Parsons, A||Palmer, DM||Smith, PJ

publication date

  • May 2009