HUBBLE-SPACE-TELESCOPE ULTRAVIOLET SPECTROSCOPY OF THE HIGHLY POLARIZED BUT QUIESCENT QUASAR OI-287

The quasar OI 287 has a unique combination of properties, including a high and constant optical polarization oriented parallel to the radio axis, a quiescent optical flux, and a lobe-dominant radio source. The polarization suggests a relationship to the broad absorption line quas ars. It is a possible transition object which could illuminate the geo metry of active galactic nuclei generally. Previous studies have led t o the picture of an edge-on thin dusty torus occulting a featureless c ontinuum (FC) source and a broad line region (BLR) in this object. The FC source and the BLR are seen only in reflected (polarized) light. I n the unified models, this makes OI 287 a ''quasar 2,'' analogous to t he type 2 Seyfert galaxies and the narrow-line radio galaxies. Our UV spectrum adds two bits of information consistent with the above ideas. First, the spectrum neither turns up in the UV, as expected for optic ally thin dust scattering, nor turns down as expected for polarization by dust transmission. It is consistent with reflection by free electr ons or optically thick dust. Second, there are in fact blueshifted abs orption troughs associated with the C IV lambda1549 line, supporting t he analogy with BALs, as well as the idea that the BALs are objects wh ich present a nearly edge-on view of a disk structure.