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The theoretical instability strip of M dwarf stars

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 نشر من قبل Cristina Rodriguez-Lopez
 تاريخ النشر 2013
  مجال البحث فيزياء
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The overstability of the fundamental radial mode in M dwarf models was theoretically predicted by Rodriguez-Lopez et al. (2012). The periods were found to be in the ranges ~25-40 min and ~4-8 h, depending on stellar age and excitation mechanism. We have extended our initial M dwarf model grid in mass, metallicity, and mixing length parameter. We have also considered models with boundary conditions from PHOENIX NextGen atmospheres to test their influence on the pulsation spectra. We find instability of non-radial modes with radial orders up to k=3, degree l=0-3, including p and g modes, with the period range extending from 20 min up to 11 h. Furthermore, we find theoretical evidence of the potential of M dwarfs as solar-like oscillators.



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