Very high column density and small reddening towards GRB 020124 at z = 3.20

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

23 pages, 6 figures, ApJ, in press

Scientific paper

10.1086/378493

We present optical and near-infrared observations of the dim afterglow of GRB 020124, obtained between 2 and 68 hours after the gamma-ray burst. The burst occurred in a very faint (R > 29.5) Damped Ly-alpha Absorber (DLA) at a redshift of z = 3.198 +- 0.004. The derived column density of neutral hydrogen is log(N_H) = 21.7 +- 0.2 and the rest-frame reddening is constrained to be E(B-V) < 0.065, i.e., A_V < 0.20 for standard extinction laws with R_V ~ 3. The resulting dust-to-gas ratio is less than 11 % of that found in the Milky Way, but consistent with the SMC and high-redshift QSO DLAs, indicating a low metallicity and/or a low dust-to-metals ratio in the burst environment. A grey extinction law (large R_V), produced through preferential destruction of small dust grains by the GRB, could increase the derived A_V and dust-to-gas ratio. The dimness of the afterglow is however fully accounted for by the high redshift: If GRB 020124 had been at z = 1 it would have been approximately 1.8 mag brighter--in the range of typical bright afterglows.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Very high column density and small reddening towards GRB 020124 at z = 3.20 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Very high column density and small reddening towards GRB 020124 at z = 3.20, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Very high column density and small reddening towards GRB 020124 at z = 3.20 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-151573

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.