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Pulsations induced by deuterium-burning in young brown dwarfs

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 نشر من قبل Francesco Palla
 تاريخ النشر 2005
  مجال البحث فيزياء
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Very low-mass stars and brown dwarfs can undergo pulsational instability excited by central deuterium burning during the initial phases of their evolution. We present the results of evolutionary and nonadiabatic linear stability models that show the presence of unstable fundamental modes. The pulsation periods vary bewteen ~5 hr for a 0.1 Msun star and ~1 hr for a 0.02 M$_odot$ brown dwarf. The results are rather insensitive to variations in the input physics of the models. We show the location of the instability strip in the HR and c-m diagrams and discuss the observational searches for young pulsators in nearby star forming regions.



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