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We observed an entire 1.7 day orbit of the X-ray binary Hercules X-1 with theFar Ultraviolet Spectroscopic Explorer (FUSE). Changes in the O VI 1032,1037line profiles through eclipse ingress and egress indicate a Keplerian accretiondisk spinning prograde with the orbit. These observations may show the firstdouble-peaked accretion disk line profile to be seen in the Hercules X-1system. Doppler tomograms of the emission lines show a bright spot offset fromthe Roche lobe of the companion star HZ Her, but no obvious signs of theaccretion disk. Simulations show that the bright spot is too far offset fromthe Roche lobe to result from uneven X-ray heating of its surface. The absenceof disk signatures in the tomogram can be reproduced in simulations whichinclude absorption from a stellar wind. We attempt to diagnose the state of theemitting gas from the C III 977, C III 1175, and N III 991 emission lines. Thelatter may be enhanced through Bowen fluorescence.

FUSE Observations of a Full Orbit of Hercules X-1: Signatures of Disk, Star, and Wind