The X-Ray Photo-ionized Wind in Cen X-3/V779 Cen

We present a high resolution spectrum of Cen X-3 obtained over an eclipse with Chandra/HETGS. The line flux ratios in helium-like triplets confirm our interpretation that the emission lines are due to recombination in a photoionized plasma. The line fluxes indicate that the wind was less highly ionized and less dense than in an earlier observation with ASCA. Preliminary results suggest that the velocity of the wind derived from line shifts and line widths is lower than that of winds in isolated O stars and so the mass-loss rate is also less than that for isolated O stars. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.