%0 Generic %1 fukugita2014nature %A Fukugita, Masataka %A Ménard, Brice %D 2014 %K absorption dlas dust %T The nature of Damped Lyman-\alpha and MgII absorbers explored with their dust contents %U http://arxiv.org/abs/1403.4339 %X We estimate the abundance of dust in damped Lyman-\alpha absorbers (DLA) by statistically measuring the excess reddening they induce on their background quasars. We detect systematic reddening behind DLA consistent with the SMC type reddening curve, but it is inconsistent with the Milky Way type reddening. We find that metallicity derived from the dust abundance, on average, anticorrelates with the column density of neutral hydrogen, <Z> ~ 1/N, meaning that the column density of metals HI is constant irrespective of the column density of hydrogen. This indicates that the prime origin of metals seen in damped Lyman-\alpha absorbers is not by in situ star formation, with which <Z> ~ N^0.4 is HI expected from the empirical star formation law, contrary to our observation. We interpret the metals observed in absorbers being deposited dominantly from nearby galaxies by galactic winds ubiquitous in intergalactic space. We find that this metallicity H I column density relation for damped Lyman-\alpha clouds extrapolates to Mg II clouds.

@misc{fukugita2014nature, abstract = {We estimate the abundance of dust in damped Lyman-{\alpha} absorbers (DLA) by statistically measuring the excess reddening they induce on their background quasars. We detect systematic reddening behind DLA consistent with the SMC type reddening curve, but it is inconsistent with the Milky Way type reddening. We find that metallicity derived from the dust abundance, on average, anticorrelates with the column density of neutral hydrogen, <Z> ~ 1/N, meaning that the column density of metals HI is constant irrespective of the column density of hydrogen. This indicates that the prime origin of metals seen in damped Lyman-{\alpha} absorbers is not by in situ star formation, with which <Z> ~ N^0.4 is HI expected from the empirical star formation law, contrary to our observation. We interpret the metals observed in absorbers being deposited dominantly from nearby galaxies by galactic winds ubiquitous in intergalactic space. We find that this metallicity H I column density relation for damped Lyman-{\alpha} clouds extrapolates to Mg II clouds.}, added-at = {2014-03-19T10:14:56.000+0100}, author = {Fukugita, Masataka and Ménard, Brice}, biburl = {https://www.bibsonomy.org/bibtex/2f1bdc60c5d47111e322713ccae423b1b/miki}, description = {[1403.4339] The nature of Damped Lyman-{\alpha} and MgII absorbers explored with their dust contents}, interhash = {d3869d7e0f9da410784fdddc0bd2e755}, intrahash = {f1bdc60c5d47111e322713ccae423b1b}, keywords = {absorption dlas dust}, note = {cite arxiv:1403.4339Comment: 8 pages, 5 figures}, timestamp = {2014-03-19T10:14:56.000+0100}, title = {The nature of Damped Lyman-{\alpha} and MgII absorbers explored with their dust contents}, url = {http://arxiv.org/abs/1403.4339}, year = 2014 }