Search for: All records

The circumgalactic medium (CGM) plays a vital role in the formation and evolution of galaxies, acting as a lifeline between galaxies and the surrounding intergalactic medium. In this study, we leverage a unique sample of quasar pairs to investigate the properties of the CGM with absorption line tomography. We present a new sample of medium-resolution Keck/ESI, Magellan/MagE, and VLT/XSHOOTER spectra of 29 quasar pairs at redshift 2 <z< 3. We supplement the sample with additional spectra of 32 pairs from the literature, creating a catalog of 61 quasar pairs with angular separations between 1.″7 and 132.″9 and projected physical separations (r_⊥) between 14 kpc and 887 kpc. We construct a catalog of 906 metal-line absorption doublets of Civ(λλ1548, 1550) with equivalent widths ranging from 6 m Å ≤W_r,1550≤ 2053 m Å. The best-fit linear model to the log-space equivalent width frequency distribution ($\log f(W_r)=m\log (W_r)+b$) of the sample yields coefficients ofm= −1.44 ± 0.16 andb= −0.43 ± 0.16. To constrain the projected extent of Civ, we calculate the transverse autocorrelation function. The flattening of the autocorrelation function at lowr_⊥provides a lower limit for the coherence length of the metal enriched CGM—on the order ofmore »200h⁻¹comoving kpc. This physical size constraint allows us to refine our understanding of the metals in the CGM, where the extent of Civin the CGM depends on gas flows, feedback, timescale of metal injection and mixing, and the mass of the host galaxies.