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We have used archival Chandra and XMM-Newton observations of quasars hostingintrinsic narrow UV absorption lines (intrinsic NALs) to carry out anexploratory survey of their X-ray properties. Our sample consists of threeintrinsic-NAL quasars and one "mini-BAL" quasar, plus four quasars withoutintrinsic absorption lines for comparison. These were drawn in a systematicmanner from an optical/UV-selected sample. The X-ray properties ofintrinsic-NAL quasars are indistinguishable from those of "normal" quasars. Wedo not find any excess absorption in quasars with intrinsic NALs, with upperlimits of a few times 10^22 cm^-2. We compare the X-ray and UV properties ofour sample quasars by plotting the equivalent width and blueshift velocity ofthe intrinsic NALs and the X-ray spectral index against the "optical-to-X-ray"slope, alpha-ox. When BAL quasars and other AGNs with intrinsic NALs areincluded, the plots suggest that intrinsic-NAL quasars form an extension of theBAL sequences and tend to bridge the gap between BAL and "normal" quasars.Observations of larger samples of intrinsic-NAL quasars are needed to verifythese conclusions. We also test two competing scenarios for the location of theNAL gas in an accretion-disk wind. Our results strongly support a location ofthe NAL gas at high latitudes above the disk, closer to the disk axis than thedense BAL wind. We detect excess X-ray absorption only in Q0014+8118, whichdoes not host intrinsic NALs. The absorbing medium very likely corresponds toan intervening system at z=1.1, which also produces strong absorption lines inthe rest-frame UV spectrum of this quasar. In the appendix we discuss theconnection between UV and X-ray attenuation and its effect on alpha-ox.

Exploratory Study of the X-Ray Properties of Quasars With Intrinsic Narrow Absorption Lines