Proximate Molecular Quasar Absorbers: Excess of damped H2 systems at zabs~zQSO in SDSS DR14

We present results from a search for strong H2 absorption systems proximate to quasars (zabs~zem) in the Sloan Digital Sky Survey (SDSS) Data Release 14. The search is based on the Lyman-Werner band signature of damped H2 absorption lines without any prior on the associated metal or neutral hydrogen content. This has resulted in the detection of 81 systems with log N(H2)~19-20 located within a few thousand km/s from the quasar. Compared to a control sample of intervening systems, this implies an excess of proximate H2 systems by about a factor of 4 to 5. The incidence of H2 systems increases steeply with decreasing relative velocity, reaching an order of magnitude higher than expected from intervening statistics at Delta_v
accepted for publication in A&A