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arXiv · 0908.3658

Star Cluster Dissolution in Arp 284

Bradley W. Peterson·Curtis Struck·Beverly J. Smith·Mark Hancock
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Abstract

We present results from a study of proto-globular cluster candidates in the interacting galaxy system Arp 284 (NGC 7714/5). Studies of the Antennae and M51 have suggested that the majority of these star clusters dissolve within 20 Myr due to mass loss. We obtain cluster colors using archival \emph{HST} data, and estimate ages and extinctions for over 150 clusters using evolutionary synthesis models. We find that clusters in NGC 7714 are generally less than 20 Myr old, while the data in the bridge is too limited to allow good estimates for individual clusters. We also examine {H {\sc ii}} region complexes with lower-resolution \emph{GALEX} and ground-based H$α$ images. Several of these regions appear to be much older than the detected clusters within them, which may indicate the presence of an older, unresolved population of low mass or dispersed clusters.

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Bradley W. Peterson, Curtis Struck, Beverly J. Smith, Mark Hancock. 2009-08-25. Star Cluster Dissolution in Arp 284. https://arxiv.org/abs/0908.3658

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