2001ApJ...553L.101G

We present two low-resolution (R∼1300) high signal-to-noise ratio spectra (W_r,lim~50 mÅ) of the quasar CSO 118 (z_em=2.97) taken with the Hobby-Eberly Telescope Marcario Low-Resolution Spectrograph. We detect eight absorbers selected by the C IV λλ1548, 1550 absorption doublet in the redshift range 2.23≲z_abs≲2.97, seven of which are z_abs≳2.68. In the redshift range covered by the seven z_abs≳2.68 systems, one expects to find two absorbers. We discuss possible explanations for such an excess of absorbers in a small velocity range. Only superclustering at high redshift and absorption due to intrinsic gas are feasibly allowed.