The clustering of galaxies around three damped Ly-alpha absorbers at Redshift Three

Abstract

[Abridged] We present out results on the cross-correlation of Lyman break galaxies (LBGs) around three damped \Ly absorbers (DLAs) at redshift three from deep multi-band MOSAIC images obtained at the KPNO 4m. The large area of the MOSAIC images, 0.31 $\deg^2$ allows us to probe the clustering of LBGs on scales up to 20 Mpc co-moving to test whether DLA halos are more or less massive than LBG halos. . We present our survey that covers a total of 1 deg$^2$ and contains $\sim$3,000 LBGs with photometric redshifts between 2.8 and 3.5. Within a redshift slice of width $W_z=0.15$, we find that the DLA-LBG cross-correlation is $1.6\pm 1.3$ times the LBG-LBG autocorrelation. This corresponds to a correlation length of $r_o=5\pm4.5h^{-1}$ (co-moving). The cross-correlation is most significant on scales 5-10 Mpc, and is significantly greater than zero at the $>95$% level from Monte Carlo simulations.