Discovery of Associated Absorption Lines in an X-ray Warm Absorber: HST Observations of PG1114+445

Abstract

The unified picture of X-ray/UV absorbers offers an unique opportunity to probe the nuclear environment of AGNs. To test the unified absorber scenario and to understand the physical properties of the absorber we obtained the first UV spectrum of PG1114+445, using HST FOS. PG1114+445 is known to have an X-ray ionized (``warm'') absorber, so that UV absorption is predicted. The HST spectrum clearly shows strong UV absorption lines due to Lya, CIV and NV, blueshifted by ~600 km/s with respect to the quasar redshift. Since both X-ray and UV absorbers are rare in radio-quiet quasars, these observations argue strongly that the X-ray and UV absorbers are closely physically related, probably identical. We place constraints on the parameters of the absorber and conclude that the mass outflow rate is comparable to the accretion rate in PG1114+445.