Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8141171 | New Astronomy | 2019 | 5 Pages |
Abstract
The damped and sub-damped Lyα systems (DLAs and sub-DLAs) traced in absorption against bright background quasars represent the main reserve of neutral hydrogen at high redshifts. We used the archival Very Large Telescope (VLT) instrument Ultraviolet and Visual Echelle Spectrograph (UVES) high-resolution data of Q 0338-0005 (zem=3.049) to study the abundances of the DLA (zabs=2.2298) and sub-DLA (zabs=2.7457) along the line of sight. We estimated column densities of H i and various elements present in the DLA and sub-DLA through Voigt profile fitting. The DLA throgh shows the Lyα emission from its host galaxy. We derive the metallicities of the DLA and sub-DLA with [Zn/H] =â0.67±0.18 and [S/H] =â1.45±0.17, respectively. We compared our abundances of the DLA and sub-DLA with other high-resolution DLA and sub-DLA metallicities and find that both populations show an overall increase of metallicity with decreasing redshift. However, sub-DLAs have higher metallicities than the DLAs.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Astronomy and Astrophysics
Authors
Waqas Bashir, Tayyaba Zafar, Fazeel M. Khan, Farrukh Chishtie,