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Lenticular galaxies at the outskirts of the Leo II group: NGC 3599 and NGC 3626

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 نشر من قبل Alexei Moiseev
 تاريخ النشر 2010
  مجال البحث فيزياء
والبحث باللغة English
 تأليف O. K. Silchenko




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We have studied unbarred S0 galaxies, NGC 3599 and NGC 3626, the members of the X-ray bright group Leo II, by means of 3D spectroscopy, long-slit spectroscopy, and imaging, with the aim to identify epoch and mechanismsof their transformation from spirals. Both galaxies have appeared to bear a complex of features resulting obviously from minor merging: decoupled gas kinematics, nuclear starforming rings, and multi-tiered oval large-scale stellar disks. The weak-emission line nucleus of NGC 3599 bears all signs of the Seyfert activity, according to the line-ratio diagnostics of the gas excitation mechanism. After all, we conclude that the transformation of these lenticular galaxies has had place about 1-2 Gyr ago, through the gravitational mechanisms not related to hot intragroup medium of Leo II.



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