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arXiv · 1404.1562

Ionized Gas Kinematics at High Resolution IV: Star Formation and a Rotating Core in the Medusa (NGC 4194)

Sara C. Beck·John Lacy·Jean Turner·Thomas Greathouse·Susan Neff
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Abstract

NGC 4194 is a post-merger starburst known as The Medusa for its striking tidal features. We present here a detailed study of the structure and kinematics of ionized gas in the central 0.65 kpc of the Medusa. The data include radio continuum maps with resolution up to $0.18\arcsec$ (35 pc) and a $12.8μ$m [NeII] data cube with spectral resolution $\sim4$\kms: the first {\it high resolution, extinction-free} observations of this remarkable object. The ionized gas has the kinematic signature of a core in solid-body rotation. The starburst has formed a complex of bright compact \HII~regions, probably excited by deeply embedded super star clusters, but none of these sources is a convincing candidate for a galactic nucleus. The nuclei of the merger partners that created the Medusa have not yet been identified.

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Sara C. Beck, John Lacy, Jean Turner, Thomas Greathouse, Susan Neff. 2014-04-06. Ionized Gas Kinematics at High Resolution IV: Star Formation and a Rotating Core in the Medusa (NGC 4194). https://doi.org/10.1088/0004-637x%2F787%2F1%2F85

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