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A Search for Intra-group Planetary Nebulae in the M 81 Group

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 نشر من قبل John Feldmeier
 تاريخ النشر 2001
  مجال البحث فيزياء
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 تأليف John J. Feldmeier




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We present the initial results from an [O III] lambda 5007 survey for intra-group planetary nebulae in the M 81 group of galaxies. A total of 0.36 square degrees of the survey have been analyzed thus far, and a total of four intra-group candidates have been detected. These data allow us to probe the physics of galaxy interactions in small groups, and give us an upper limit for the density of intracluster starlight. We find that the M 81 group has less than 3% of its stars in an intra-group component; this is much less than the fraction found in richer galaxy clusters.



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