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A search for wide brown dwarf companions to stars within 10pc

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 نشر من قبل Andreas Seifahrt
 تاريخ النشر 2008
  مجال البحث فيزياء
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We present the first results of a large imaging survey to identify wide brown dwarf companions to stars within 10 pc. We have performed a deep (H-band limit ~ 19.0 mag), wide field (up to 16x16 arcmin) astrometric imaging campaign in two epochs around more than 230 nearby stars. Preliminary results show that the wide low-mass companion fraction is far lower than expected, indicating that interactions with the galactic disk may have removed the weakly bound wide companions around old stars.



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