Optical spectroscopy of the quiescent counterpart to EXO 0748-676: a black widow scenario?

  title={Optical spectroscopy of the quiescent counterpart to EXO 0748-676: a black widow scenario?},
  author={E. M. Ratti and D Steeghs and Peter G. Jonker and Manuel A. P. Torres and C.G.Bassa and Frank Verbunt},
  journal={Monthly Notices of the Royal Astronomical Society},
We present phase-resolved optical spectroscopy of the counterpart to the neutron star low mass X-ray binary EXO 0748-676, almost one year after it turned into quiescence. The spectra display prominent Hbeta and Hgamma and weak Fe II lines in emission. An average of all the spectra (corrected for the orbital motion) also exhibits a very weak line from Mg I. Tomographic reconstructions show that the accretion disc is not contributing to the optical line emission, which is instead dominated by the… Expand

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