Abstract
view Abstract Citations (143) References (57) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Metal Enrichment, Dust, and Star Formation in Galaxies at High Redshifts. I. The Z = 2.3091 Absorber toward PHL 957 Pettini, Max ; Boksenberg, Alec ; Hunstead, Richard W. Abstract We present the first results from a survey aimed at determining the degree of metal enrichment, the dust content, and the star formation rate of QSO absorption systems with damped Lyα lines. This class of absorbers is thought to arise in the high-redshift progenitors of present-day disk galaxies. We show how measurements of weak absorption lines of Zn lI--detected here for the first time in a QSO spectrum--and of Cr II can provide accurate estimates of the metallicity and an indication of the dust-to-gas ratio, while an informative upper limit on the star formation rate can be obtained by searching for weak emission in the core of the damped Lyα line. The z_abs_ = 2.3091 system in PHL 957 has both a low metal abundance, 24 times below solar, and a low dust-to-gas ratio, approximately one order of magnitude lower than values typical of local interstellar clouds. These results suggest that the absorption system arises in a galaxy at an early stage of chemical evolution. The star formation rate is less than ~ 30 M_sun_ yr^-1^. These and other parameters are strikingly similar to those of nearby H II galaxies and, if found by future work to be typical of the damped Lyα sample in general, would suggest that disk galaxies at z ~ 2.5 resembled closely the H II galaxies we see today. Alternatively, the damped Lyα lines may arise predominantly in dwarf galaxies whose properties have not changed significantly from z ~ 2.5 to the present epoch. Further observations of damped Lyα systems should allow us to distinguish between these two possibilities and offer excellent opportunities for measuring the primordial abundance of deuterium. Publication: The Astrophysical Journal Pub Date: January 1990 DOI: 10.1086/168212 Bibcode: 1990ApJ...348...48P Keywords: Cosmic Dust; H Ii Regions; Metallicity; Quasars; Red Shift; Star Formation; Disk Galaxies; Galactic Evolution; Interstellar Matter; Lyman Alpha Radiation; Astrophysics; GALAXIES: FORMATION; GALAXIES: INTERSTELLAR MATTER; NEBULAE: H II REGIONS; QUASARS full text sources ADS | data products SIMBAD (6) NED (2) Related Materials (2) Part 2: 1990ApJ...356...23H Part 3: 1994ApJ...426...79P
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
