X-ray diagnostics of massive star winds

摘要: Abstract Nearly all types of massive stars with radiatively driven stellar winds are X-ray sources that can be observed by the presently operating powerful telescopes. In this review I briefly address recent advances in our understanding obtained from observations. X-rays may strongly influence dynamics weak main sequence B-type stars. pulsations were detected a β Cep type variable giving evidence tight photosphere-wind connections. The OB dwarfs subtypes later than O9V predominantly hot phase, and observations offer best window for their studies. properties supergiants largely determined effects radiative transfer clumped winds. recently suggested method to directly measure mass-loss rates O fitting shapes emission lines is considered but its validity cannot confirmed. To obtain robust quantitative information on wind parameters spectroscopy, multiwavelength analysis means atmosphere models required. Independent groups now performing such analyses encouraging results. Joint optical, UV, spectra yield consistent rates. Depending adopted clumping parameters, empirically derived factor few smaller or comparable those predicted standard recipes (Vink et al., 2001). All sufficiently studied display might related corotating interaction regions latest stages evolution, single red (RSG) luminous blue (LBV) do not emit observable amounts X-rays. On other hand, nearly Wolf–Rayet (WR) sources. spectroscopy allows sensitive probe WR abundances opacities.