Mathematics – Probability
Scientific paper
Sep 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006head....9.0131v&link_type=abstract
American Astronomical Society, HEAD meeting #9, #1.31; Bulletin of the American Astronomical Society, Vol. 38, p.334
Mathematics
Probability
Scientific paper
The Space Telescope Imaging Spectrograph on Hubble provides the highest resolution ultraviolet spectra ever taken of Cyg X-1. In observations taken at four orbital phases during the X-ray intermediate state we detect P Cygni profiles from both high ionization (N V, C IV, Si IV) and low ionization (O I, C II, Si II, Fe II, Al II) material. We show that the orbital variation in the UV P Cygni lines of Cygnus X-1 results when X-rays photoionize the region outside of the X-ray shadow of the normal star. Analytic methods assuming a spherically symmetric wind show that the wind velocity law is well fitted by v (1-1/r)^beta. Escape probability models can fit the observed P Cygni profiles and provide measurements of the stellar wind parameters. The fits imply L_X/M=2.9+/-0.2x10^44 ergs s^-1, M^-1_solar year, where L_X is the X-ray luminosity and M is the mass-loss rate of the star. This corresponds well to X-ray luminosities measured by Chandra at spectral states similar to those of the HST observations. We discuss the implications of our results for the presence of a `focused' wind in Cygnus X-1.
Boroson Bram Seth
Hunacek Adrienne
Vrtilek Saeqa D.
No associations
LandOfFree
X-Ray Ionization Effects on the Stellar Wind of Cygnus X-1 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with X-Ray Ionization Effects on the Stellar Wind of Cygnus X-1, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and X-Ray Ionization Effects on the Stellar Wind of Cygnus X-1 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-776359