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Methane T-Dwarf Candidates in the Star Forming Region IC 348

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 نشر من قبل Jerome Bouvier
 تاريخ النشر 2008
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Andrew Burgess




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IC 348 is a young (t$sim$3Myr) and nearby (d$sim$340pc) star forming region in the Perseus molecular cloud. We performed a deep imaging survey using the MEGACAM (z-band) and WIRCAM (JHK and narrowband CH${_4}$ on/off) wide-field cameras on the Canada-France-Hawaii Telescope. From the analysis of the narrowband CH${_4}$ on/off deep images, we report 4 T-dwarf candidates, of which 3 clearly lie within the limits of the IC 348 cluster. An upper limit on the extinction was estimated for each candidate from colour-magnitude diagrams, and found consistent with extinction maps of the cloud. Initial comparisons with T-dwarf spectral models suggest these candidates have a spectral type between T3 and T5, and perhaps later, potentially making these among the lowest mass isolated objects detected in a young star forming region so far.



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