Formation of eccentric gas discs from sublimating or partially disrupted asteroids orbiting white dwarfs

  title={Formation of eccentric gas discs from sublimating or partially disrupted asteroids orbiting white dwarfs},
  author={David Trevascus and Daniel J. Price and Rebecca Nealon and David Liptai and Christopher J. Manser and Dimitri Veras},
Of the 21 known gaseous debris discs around white dwarfs, a large fraction of them display observational features that are well described by an eccentric distribution of gas. In the absence of embedded objects or additional forces, these discs should not remain eccentric for long timescales, and should instead circularise due to viscous spreading. The metal pollution and infrared excess we observe from these stars is consistent with the presence of tidally disrupted sub-stellar bodies. We… 

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