NICER observation list: Target ID 560701

Cyg X-1 is in a 5.6 day orbit around a High Mass X-ray Binary that donates mass to the black hole system via ``focused wind accretion''. Near orbital phase 0, or line of sight to the inner accretion flow passes through this wind, and allows X-rays from the black hole to probe the wind's structure. Historically, we see ``dips'' associated with both highly ionized absorption and colder, denser near neutral absorption. NICER, with its large effective area, superb soft X-ray response, and low background is uniquely suited to study this dipping behavior on time scales potentially as fast as 0.1 s. We will use modeling of light curves, time-dependent color-color diagrams, and spectra at different color/flux levels.