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arXiv · 1403.5559

The extent of the MgII absorbing circum-galactic medium of quasars

E. P. Farina·R. Falomo·R. Scarpa·R. Decarli·A. Treves·J. K. Kotilainen
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Abstract

We investigate the extent and the properties of the MgII cool, low-density absorbing gas located in the halo and in the circum-galactic environment of quasars, using a sample of 31 projected quasar pairs with impact parameter pd<200kpc in the redshift range 0.5 0.3Ang. ranges from fc~1.0 at pd<65kpc to fc~0.2 at pd>150kpc, and appears to be higher than for galaxies. Our findings support a scenario where the luminosity/mass of the host galaxies affect the extent and the richness of the absorbing MgII circum-galactic medium.

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E. P. Farina, R. Falomo, R. Scarpa, R. Decarli, A. Treves, J. K. Kotilainen. 2014-03-21. The extent of the MgII absorbing circum-galactic medium of quasars. https://doi.org/10.1093/mnras%2Fstu585

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