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Measuring the halo mass of MgII absorbers from their cross-correlation with Luminous Red Galaxies

Nicolas Bouche·M. T. Murphy·C. Peroux·I. Csabai
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Abstract

We study the cross-correlation between 716 MgII quasar absorption systems and about 100,000 Luminous Red Galaxies (LRGs) selected from the Sloan Digital Sky Survey Data Release 3 in the redshift range 0.4<z<0.8. The MgII systems were selected to have 2796 & 2803 rest-frame equivalent widths greater than 1.0 Åand identifications confirmed by the FeII 2600 or MgI 2852 lines. Over co-moving scales 0.2--13/h Mpc, the MgII--LRG cross-correlation has an amplitude 0.69+/-0.09 times that of the LRG--LRG auto-correlation. Since LRGs have halo-masses of 10^{13} \msun, this strong cross-correlation implies that the absorber host-galaxies have halo-masses 1--2 times 10^{12} \msun.

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Nicolas Bouche, M. T. Murphy, C. Peroux, I. Csabai. 2005-04-25. Measuring the halo mass of MgII absorbers from their cross-correlation with Luminous Red Galaxies. https://doi.org/10.1017/s1743921305002899

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