2000ApJ...531..654P

We have studied a spectrum of Q0122+0338 (z_e∼1.202) obtained by the Faint Object Spectrograph (FOS) on board the Hubble Space Telescope (HST). We present the analysis of three associated (z_a∼z_e) absorption systems at z=1.207, 1.199, and 1.166. The most complex of these, at z_a∼1.207, shows strong absorption from the highly ionized transitions of Lyα, Lyβ, N V, O VI, Si III, Si IV, and possibly P V. We derive (minimal) ionic column densities for this system of N(H I)=10^15.3 cm^–2, N(N V)=10^14.8 cm^–2, N(O VI)=10^15.4 cm^–2, N(Si III)=10^13.3 cm^–2, and N(Si IV)=10^13.7 cm^–2. By comparing the derived column densities with those predicted from numerical photoionization models, we find that conditions in the absorbing gas are consistent with an absorber with a metallicity ∼2 Z_☉ and a total absorbing column density of N(H)≃2x10¹⁹ cm^–2. The kinematics of the absorption lines in the z_a∼1.207 system suggests that a correlation exists between the relative velocity and the creation ionization potential energy for each transition. This is evidence that a complex, multicomponent absorber exists. Although the location of the absorber is uncertain (intrinsic vs. intervening), we consider the origin of this absorption system using the available data and discuss how the high ionization and high metallicity indicate that the absorber may be intrinsic to Q0122+0338.