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The Sombrero Galaxy III. Ionised gas and dust in the central 200 pc: a nuclear bar?

Eric Emsellem·Pierre Ferruit
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Abstract

We present the results of new 3D TIGER spectroscopic observations and archived HST/WFPC2 and NICMOS images of the central region of M 104. The [NII]+Ha images reveal the presence of a nuclear spiral structure, and the gaseous kinematics in the central arcsecond shows evidence for kinematical decoupling of the central peak. A straight nuclear dust lane, with a weak symmetric counterpart, is seen in the V-I and V-H colour maps. These results hint for the presence of a strong nuclear bar, that would be located inside the inner Linblad resonance of the large-scale bar discussed by Emsellem (1995).

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Eric Emsellem, Pierre Ferruit. 2000-03-13. The Sombrero Galaxy III. Ionised gas and dust in the central 200 pc: a nuclear bar?. https://arxiv.org/abs/astro-ph/0003167

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