Séminaire Univers / |
| « Confirming the metallicity-luminosity relation for high-redshift absorption-selected galaxies » |
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Jens-Kristian Krogager |
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Damped Lyman-alpha absorbers (DLAs) provide a powerful and precise method for studying the metallicity evolution at high redshift, and reveal detailed information about kinematics of the absorbing gas. However, for many years the physical nature of the galaxies in which the absorption arises has been mostly unknown, especially in terms of fundamental properties such as their sizes, masses, and star formation rates. Recently, the situation at high redshift has changed thanks to near-IR spectrographs (X-shooter and SINFONI in particular). In this talk I will present recent results from our survey targeting high-metallicity DLAs with X-shooter in order to search for emission counterparts of the absorption.
We find a high detection rate (7/11) in our high-metallicity sample, significantly higher than studies of blindly selected DLAs. Comparing the results, as well as previous literature studies, to a model in which DLA absorption arises from low-luminosity star-forming galaxies, we demonstrate that DLAs follow a relation between metallicity and luminosity. Moreover, we highlight the future prospectives of using DLAs as probes of the low-luminosity end of the luminosity function in the distant Universe. |
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mardi 13 juin 2017 - 11:15 Salle 281 Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |