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arXiv · 1006.4717

NGC 4262: a Virgo galaxy with an extended ultraviolet ring

Bettoni·D.·Buson·L. M.·Galletta·G.
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Abstract

The Galaxy Ultraviolet Explorer (GALEX) satellite has recently shown the presence of an extended, outer ring studded with UV-bright knots surrounding the lenticular galaxy NGC 4262. Such a structure---not detected in the optical---is coupled with a ring of atomic (HI) gas. We want to show that both star-forming and HI rings surrounding this SB0 galaxy share the same radial distance from the galaxy center and spatial orientation. We want also to model the kinematics of the ring(s) and of the galaxy body. We make use of archive FUV and NUV GALEX data plus HI observations from the literature. We confirm that the UV-bright and atomic gas rings of NGC 4262 have the same extent and projected spatial orientation. Their kinematics is not coupled with that of the galaxy stars. It is possible that NGC 4262 has undergone a major gas stripping event in the past which gave origin to the present "necklace" of UV-bright knots.

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Bettoni, D., Buson, L. M., Galletta, G.. 2010-06-24. NGC 4262: a Virgo galaxy with an extended ultraviolet ring. https://arxiv.org/abs/1006.4717

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