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arXiv · 0801.1213

The Central Region of M83

R. C. W. Houghton·N. Thatte
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Abstract

We combine VLT/ISAAC NIR spectroscopy with archival HST/WFPC2 and HST/NICMOS imaging to study the central 20"x20" of M83. Our NIR indices for clusters in the circumnuclear star-burst region are inconsistent with simple instantaneous burst models. However, models of a single burst dispersed over a duration of 6 Myrs fit the data well and provide the clearest evidence yet of an age gradient along the star forming arc, with the youngest clusters nearest the north-east dust lane. The long slit kinematics show no evidence to support previous claims of a second hidden mass concentration, although we do observe changes in molecular gas velocity consistent with the presence of a shock at the edge of the dust lane.

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R. C. W. Houghton, N. Thatte. 2008-01-08. The Central Region of M83. https://doi.org/10.1111/j.1365-2966.2008.12893.x

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