Wind ionization structure of the short-period eclipsing LMC Wolf-Rayet binary BAT99-129: preliminary results

Abstract

BAT99-129 is a rare, short-period eclipsing Wolf-Rayet binary in the Large Magellanic Cloud. We present here medium-resolution NTT/EMMI spectra that allow us to disentangle the spectra of the two components and find the orbital parameters of the binary. We also present VLT/FORS1 spectra of this binary taken during the secondary eclipse, i.e. when the companion star passes in front of the Wolf-Rayet star. With these data we are able to extract, for the first time in absolute units for a WR+O binary, the sizes of the line emitting regions.

6 pages, 5 figures, to appear in proc. of "Close Binaries in the 21st Century: New Opportunities and Challenges", 2005 - Corrected Figure 3