Redshifted emission lines and radiative recombination continuum from the Wolf-Rayet binary theta Muscae: evidence for a triplet system?

  title={Redshifted emission lines and radiative recombination continuum from the Wolf-Rayet binary theta Muscae: evidence for a triplet system?},
  author={Y. Sugawara and Y. Tsuboi and Y. Maeda},
  journal={arXiv: Astrophysics},
We present XMM-Newton observations of the WC binary Theta Muscae (WR 48), the second brightest Wolf-Rayet binary in optical wavelengths. The system consists of a short-period (19.1375 days) WC5/WC6 + O6/O7V binary and possibly has an additional O supergiant companion (O9.5/B0Iab) which is optically identified at a separation of ~46 mas. Strong emission lines from highly ionized ions of C, O, Ne, Mg, Si, S, Ar, Ca and Fe are detected. The spectra are fitted by a multi-temperature thin-thermal… Expand

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