Peering into the dark side: magnesium lines establish a massive neutron star in PSR J2215+5135

  title={Peering into the dark side: magnesium lines establish a massive neutron star in PSR J2215+5135},
  author={Manuel Linares and Tariq Shahbaz and Jorge Casares},
  journal={arXiv: High Energy Astrophysical Phenomena},
New millisecond pulsars (MSPs) in compact binaries provide a good opportunity to search for the most massive neutron stars. Their main-sequence companion stars are often strongly irradiated by the pulsar, displacing the effective center of light from their barycenter and making mass measurements uncertain. We present a series of optical spectroscopic and photometric observations of PSR J2215+5135, a "redback" binary MSP in a 4.14 hr orbit, and measure a drastic temperature contrast between the… 
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