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Virgo High-Resolution CO Survey :V. Circumnuclear Elliptical Ring in NGC 4569

Hiroyuki Nakanishi·Yoshiaki Sofue·Jin Koda
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Abstract

We present high-resolution ($1\farcs8$ -- $4\farcs5$) CO data of the Virgo spiral galaxy NGC 4569, obtained using the Nobeyama Millimeter Array. We found that the molecular gas is highly concentrated in the circumnuclear region with two off-center peaks. A CO image with the highest angular resolution of $2\farcs0 \times 1\farcs8$ shows that six blobs likely form a circumnuclear elliptical ring (CER) with a semi-major axis radius of 720 pc. The CER shows a strongly twisted velocity field, and the position--velocity (PV) diagram shows significant forbidden velocity components. These kinetic features are understood as being non-circular motion due to a bar-potential. We found that the CER coincides with the H$α$ bright central core and that the mass ratio of the molecular gas to the dynamical mass is about 18%. These results support a gaseous inflow scenario induced by a weak bar potential and self-gravity of the gas.

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Hiroyuki Nakanishi, Yoshiaki Sofue, Jin Koda. 2005-12-21. Virgo High-Resolution CO Survey :V. Circumnuclear Elliptical Ring in NGC 4569. https://doi.org/10.1093/pasj%2F57.6.905

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