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XMM-Newton First Observation in the Pleiades

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 نشر من قبل Kevin Briggs
 تاريخ النشر 2001
  مجال البحث فيزياء
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We present the first results from a 40 ks Guaranteed Time XMM-Newton pointing in the Pleiades. We detect almost all early-mid dM members in the field and several very low mass (VLM) stars - including the brown dwarf (BD) candidate Roque 9 - and investigate the variation of X-ray activity levels, hardness ratios and flare frequency with spectral type down to the BD regime.



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