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X-Shooter spectroscopy of brown dwarfs in the TW Hya association

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 نشر من قبل Beate Stelzer
 تاريخ النشر 2013
  مجال البحث فيزياء
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We present broad-band mid-resolution X-Shooter/VLT spectra for four brown dwarfs of the TW Hya association. Our targets comprise substellar analogs representing the different evolutionary phases in young stellar evolution: For the two diskless brown dwarfs, TWA-26 and TWA-29, we determine the stellar parameters and we study their chromospheric emission line spectrum. For the two accreting brown dwarfs, TWA-27 and TWA-28, we estimate the mass accretion rates from empirical correlations between emission line luminosities and the accretion luminosity.



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