Polarimetric evidence of a white dwarf pulsar in the binary system AR Scorpii

  title={Polarimetric evidence of a white dwarf pulsar in the binary system AR Scorpii},
  author={David A. H. Buckley and Petrus J. Meintjes and Stephen B. Potter and Thomas R. Marsh and B. T. Gansicke},
  journal={Nature Astronomy},
The variable star AR Scorpii (AR Sco) was recently discovered to pulse in brightness every 1.97 min from ultraviolet wavelengths into the radio regime. The system is composed of a cool, low-mass star in a tight, 3.55-hour orbit with a more massive white dwarf. Here we report new optical observations of AR Sco that show strong linear polarization (up to 40%) that varies strongly and periodically on both the spin period of the white dwarf and the beat period between the spin and orbital period… 

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