HZ Her: the nature and origin of the emission lines.

Abstract

The line spectrum of HZ Her/Her X-1 is investigated in highand low-dispersion IUE spectroscopy. It is noted that while velocity considerations discredit the classical sites of mission, which are the primary star's X-ray heated photosphere, accretion stream, and disk, they support an origin in discrete blobs of material orbiting at the rim of the accretion disk. A T(e) value of about 10 to the 4.4th K, together with an n(e) of about 10 to the 13.3rd/cu cm, are suggested for the blobs by an analysis of the line intensity data. It is suggested that the blobs may be identified with the material responsible for the X-ray dips.