title: High-Resolution Spectroscopy of the X-Ray-photoionized Wind in Cygnus X-3 with the Chandra High-Energy Transmission Grating Spectrometer.
abstract: We present a preliminary analysis of the 1-10 keV spectrum of the massive X-ray binary Cygnus X-3, obtained with the high-energy transmission grating spectrometer on the Chandra X-Ray Observatory. The source reveals a richly detailed discrete emission spectrum, with clear signatures of photoionization-driven excitation. Among the spectroscopic novelties in the data are the first astrophysical detections of a number of He-like "triplets" (Si, S, Ar) with emission-line ratios characteristic of photoionization equilibrium, fully resolved narrow radiative recombination continua of Mg, Si, and S, the presence of the H-like Fe Balmer series, and a clear detection of an approximately 800 km s-1 large-scale velocity field as well as an approximately 1500 km s-1 FWHM Doppler broadening in the source. We briefly touch on the implications of these findings for the structure of the Wolf-Rayet wind.
authors.initials: F
authors.lastname: Paerels
authors.initials: J
authors.lastname: Cottam
authors.initials: M
authors.lastname: Sako
authors.initials: DA
authors.lastname: Liedahl
authors.initials: AC
authors.lastname: Brinkman
authors.lastname: van Der Meer RL
authors.initials: JS
authors.lastname: Kaastra
authors.initials: P
authors.lastname: Predehl