We present the results of a spectroscopic monitoring program (from 1998 to 2002) of the Hα emission strength in HDE 226868, the optical counterpart of the black hole binary, Cyg X-1. The feature provides an important probe of the mass loss rate in the base of the stellar wind of the supergiant star. We derive an updated ephemeris for the orbit based upon radial velocities measured from He I λ6678. We list net equivalent widths for the entire Hα emission/absorption complex, and we find that there are large variations in emission strength over both long (years) and short (hours to days) time spans. There are coherent orbital phase related variations in the profiles when the spectra are grouped by Hα equivalent width. The profiles consist of (1) a P Cygni component associated with the wind of the supergiant, (2) emission components that attain high velocity at the conjunctions and that probably form in enhanced outflows both towards and away from the black hole, and (3) an emission component that moves in antiphase with the supergiant's motion. We argue that the third component forms in accreted gas near the black hole, and the radial velocity curve of the emission is consistent with a mass ratio of M X /M opt ≈ 0.36 ± 0.05. We find that there is a general anti-correlation between the Hα emission strength and X-ray flux (from the Rossi X-ray Timing Explorer All Sky Monitor instrument) in the sense that when the Hα emission is strong (W λ < −0.5Å) the X-ray flux is weaker and the spectrum harder. On the other hand, there is no correlation between Hα emission strength and X-ray flux when Hα is weak. We argue that this relationship is not caused by wind X-ray absorption nor by the reduction in Hα emissivity by Xray heating. Instead, we suggest that the Hα variations track changes in wind density and strength near the photosphere. The density of the wind determines the size of X-ray ionization zones surrounding the black hole, and these in turn control the acceleration of the wind in the direction of the black hole. During the low/hard X-ray state, the strong wind is fast and the accretion rate is relatively low, while in the high/soft state the weaker, highly ionized wind attains only a moderate velocity and the accretion rate increases. We argue that the X-ray transitions from the normal low/hard to the rare high/soft state are triggered by episodes of decreased mass loss rate in the supergiant donor star.
We present results from new optical and UV spectroscopy of the unusual binary system SS 433, and we discuss the relationship of the particular spectral components we observe to the properties of the binary. These spectral components include:(1) The continuum spectrum which we associate with flux from the super-Eddington accretion disk and the dense part of its wind. A FUV spectrum from HST/STIS 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 NUV and optical fluxes. The continuum source has a radius of approximately half the binary separation which may be larger than the Roche radius of the compact star.(2) 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
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