The mean metallicity - kinematics relation in high column density MgII absorbers and selection effects in DLA surveys

Details The mean metallicity - kinematics relation in high column density MgII absorbers and selection effects in DLA surveys The mean metallicity - kinematics relation in high column density MgII absorbers and selection effects in DLA surveys

Mar 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005pgqa.conf..104t&link_type=abstract

Probing Galaxies through Quasar Absorption Lines, IAU Colloquium Proceedings of the International Astronomical Union 199, held M

Astronomy and Astrophysics

Astronomy

12

Scientific paper

Sloan digital sky survey (SDSS) quasar spectroscopy is yielding a database of strong low-ionisation MgII absorbers over the redshift interval 0.36 which is over two orders of magnitude larger than anything previously assembled. Hubble space telescope (HST) UV spectroscopy has been used to measure neutral hydrogen column densities for a small subset of them. These data empirically show that MgII absorbers with rest equivalent widths wΛ27960 ≥ 0.6 å have a mean neutral hydrogen column density that is roughly constant at N(HI) ≈ 4×1020 atoms cm-2, with individual systems Lying in the damped Lyα (DLA) and sub-DLA regimes. Since the MgII doublets generally exhibit saturation, the wΛ27960 values are an indication of the absorbers' velocity spreads. Thus, we can study neutral-gas-phase metallicities as a function of kinematics by forming SDSS composite spectra and measuring weak unsaturated metal lines that form in neutral gas (e.g., CrII, FeII, MnII, SiII, ZnII) as a function of wΛ27960. We use this method on SDSS composite spectra to show how metallicity and kinematics are positively correlated for large-N(HI) absorbers, including trends related to dust depletion and the enhancement of α-elements. We also discuss the need to account for selection effects in DLA surveys, and we make inferences about models for DLA absorption and their contribution to cosmic star formation.

Affiliated with

Also associated with

No associations

Rating

The mean metallicity - kinematics relation in high column density MgII absorbers and selection effects in DLA surveys 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 The mean metallicity - kinematics relation in high column density MgII absorbers and selection effects in DLA surveys, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The mean metallicity - kinematics relation in high column density MgII absorbers and selection effects in DLA surveys will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1566722