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VLA HI Imaging of the brightest spiral galaxies in Coma II. The HI Atlas and deep continuum imaging of selected early type galaxies

H. Bravo-Alfaro·V. Cayatte·J. H. van Gorkom·C. Balkowski
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Abstract

In the first paper of this series we used HI observations of the 19 brightest spirals in Coma to analyze the dynamical state of the cluster. In this paper we present the detailed HI distribution and kinematics of the spirals that were detected in HI, and radio continuum data for a sample of star forming and post starburst galaxies in Coma. We discuss the importance of ICM-ISM interactions to explain the observed HI morphology. A rough comparison of observed HI sizes with predicted HI sizes from simulations by Abadi et al. (1999) gives reasonable agreement. We use the results on radio continuum emission to estimate the star formation rate in the PSB galaxies we pointed at. The radio continuum emission in the 11 so called post starburst galaxies, identified by Caldwell et al. (1993) in the cluster, is weak. Eight of the 11 were not detected down to a 3 sigma upper limit of 0.6 mJy. This sets an upper limit to the star formation rate in these galaxies of less than 0.2 solar masses per year. The three detected post starburst galaxies have a star formation rate of less than one solar mass per year. Thus none of the post starburst galaxies in Coma are dust enshrouded starbursts.

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H. Bravo-Alfaro, V. Cayatte, J. H. van Gorkom, C. Balkowski. 2001-09-19. VLA HI Imaging of the brightest spiral galaxies in Coma II. The HI Atlas and deep continuum imaging of selected early type galaxies. https://doi.org/10.1051/0004-6361%3A20011242

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