2002ApJ...566.1069G

The continuum spectrum, which we associate with flux from the super-Eddington accretion disk and the dense part of its wind. A far-UV spectrum from the Hubble Space Telescope Space Telescope Imaging Spectrograph made during the edge-on orientation of the disk places an upper limit on the temperature of an equivalent blackbody source (T<21,000 K for A_V=7.8) when combined with near-UV and optical fluxes. The continuum source has an effective projected radius of approximately half the binary separation, so that the source may be larger than the Roche radius of the compact star.

Hα moving components, which are formed far from the binary orbital plane in the relativistic jets. We confirm that these emission features appear as ``bullets'' at a fixed wavelength and may last for a few days. We present a contemporary radial velocity curve for the precessional motion of the jets that includes the nodding motion caused by tidal interaction with the optical star.

Hα and He I ``stationary'' emission lines, which we suggest are formed in the disk wind in a volume larger than the dimensions of the binary. These lines vary on all timescales and sometimes appear as P Cygni lines. We suggest that their radial velocity curves (which show greatest redshift at inferior conjunction of the optical star) result from an evacuation of the disk wind surrounding the optical star (caused by physical blockage, heating, or colliding winds). We argue that the wake of this interaction region causes an extended eclipse of the X-ray source (as seen in Rossi X-Ray Timing Explorer All-Sky Monitor light curves).

A weak ``stationary'' emission feature, which we identify as a C II λλ7231, 7236 blend that attains maximum radial velocity at the orbital quadrature of disk recession (like the velocity curve of He II λ4686). This is probably formed in outflow from the central region of the disk near the compact star.

Absorption and emission features from outflowing clumps in the disk wind (seen most clearly in an episode of blueshifted Na I emission).

We found no clear evidence of the absorption-line spectrum of the optical star, although we point out the presence of He I absorption features (blended with the stationary emission) with the expected radial velocity trend at the orbital and precessional phases when the star might best be seen.

A rich interstellar absorption spectrum of diffuse interstellar bands.