The clustering of luminous red galaxies around MgII absorbers

We study the cross-correlation between 212 MgII quasar absorption systems and similar to20000 luminous red galaxies (LRGs) selected from the Sloan Digital Sky Survey Data Release 1 in the redshift range 0 4less than or equal tozless than or equal to0 8. The Mg II systems were selected to have lambdalambda 2796 and 2803 rest-frame equivalent widths greater than or equal to1.0 Angstrom and identifications confirmed by the Fe II lambda2600 or Mg I lambda2852 lines. Over comoving scales 0.05-13 h(-1) Mpc, the Mg II-LRG cross-correlation has an amplitude 0.67+/-0.09 times that of the LRG-LRG auto-correlation. Since LRGs have halo masses greater than 3.5x10(12) M-circle dot for M(R)less than or similar to-21, this relative amplitude implies that the absorber host galaxies have halo masses greater than similar to2-8x10(11) M-circle dot. For 10(13) -M-circle dot LRGs, the absorber host galaxies have halo masses similar to0.5-2.5x10(12) M-circle dot. Our results appear consistent with those of Steidel, Dickinson & Persson (1994) who found that MgII absorbers with W(r)(Mg II)greater than or equal to0.3 are associated with similar to0.7 L-B* galaxies.