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Dynamics and Shape of Brightest Cluster Galaxies

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 نشر من قبل Heinz Andernach
 تاريخ النشر 2006
  مجال البحث فيزياء
والبحث باللغة English
 تأليف H. Andernach




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We identified Brightest Cluster Members (BCM) on DSS images of 1083 Abell clusters, derived their individual and host cluster redshifts from literature and determined the BCM ellipticity. Half the BCMs move at a speed higher than 37 % of the cluster velocity dispersion sigma_{cl}, suggesting that most BCMs are part of substructures falling into the main cluster. Both, the BCMs velocity offset in units of sigma_{cl}, and BCM ellipticity, weakly decrease with cluster richness.



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