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Proper motions of Upper Sco T-type candidates

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 نشر من قبل Nicolas Lodieu
 تاريخ النشر 2013
  مجال البحث فيزياء
والبحث باللغة English
 تأليف N. Lodieu




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We present new z- and H-band photometry and proper motion measurements for the five candidate very-low-mass T-type objects we recently proposed to be members of the nearest OB association to the Sun, Upper Scorpius. These new data fail to corroborate our prior conclusions regarding their spectral types and affiliation with the Upper Scorpius population. We conclude that we may be in presence of a turnover in the mass function of Upper Sco taking place below 10-4 Jupiter masses, depending on the age assigned to Upper Sco and the models used.



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