Whole Earth Telescope observations of BPM 37093: A seismological test of crystallization theory in white dwarfs

  title={Whole Earth Telescope observations of BPM 37093: A seismological test of crystallization theory in white dwarfs},
  author={A. Kanaan and Atsuko Nitta and Don E. Winget and S. O. Kepler and Michael H. Montgomery and Travis S. Metcalfe and et al.},
  journal={Astronomy and Astrophysics},
BPM 37093 is the only hydrogen-atmosphere white dwarf currently known which has sufficient mass (~1.1 $M_\odot$) to theoretically crystallize while still inside the ZZ Ceti instability strip ($T_{\rm eff}\sim12\,000$ K). As a consequence, this star represents our first opportunity to test crystallization theory directly. If the core is substantially crystallized, then the inner boundary for each pulsation mode will be located at the top of the solid core rather than at the center of the star… 

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