NGC 4262: a Virgo galaxy with an extended ultraviolet ring

TL;DR

This paper investigates the extended UV and HI gas rings around NGC 4262, revealing their shared spatial extent but distinct kinematics, suggesting a past gas stripping event caused the UV-bright knots.

Contribution

It demonstrates that the UV-bright and atomic gas rings in NGC 4262 share the same size and orientation but have different kinematics, indicating a past gas stripping event.

Findings

UV and HI rings share the same extent and orientation.

Kinematics of rings are decoupled from galaxy stars.

Evidence suggests a past gas stripping event.

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.