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OATS-DAUT SEMINAR
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Speaker:
Giovanni Vladilo (INAF/Osservatorio Astronomico di Trieste)
Title:
Fresh evidence of dust extinction in Damped Lyman alpha systems:
implications for the existence of metal-rich systems
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Abstract:
I present a study of reddening of quasars of
the Sloan Digital Sky Survey selected on the basis of the presence of
an intervening Damped Lyman alpha (DLA) system with detected zinc
absorption lines. The results of this study suggest the existence of a
general relation between dust extinction and metal column density
valid in DLA systems and local interstellar clouds. I discuss the
implications of this relation for our understanding of the metallicity
distribution of DLA systems and, in particular, for the existence of
metal-rich systems.
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