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arXiv · 1010.2716

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

O. K. Sil'chenko·A. V. Moiseev·A. P. Shulga
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Abstract

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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O. K. Sil'chenko, A. V. Moiseev, A. P. Shulga. 2010-10-13. Lenticular galaxies at the outskirts of the Leo II group: NGC 3599 and NGC 3626. https://doi.org/10.1088/0004-6256%2F140%2F5%2F1462

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