Star Cluster Dissolution in Arp 284

TL;DR

This study analyzes the ages and properties of proto-globular cluster candidates in the interacting galaxy system Arp 284, revealing that most clusters are younger than 20 million years and suggesting the presence of older, unresolved stellar populations.

Contribution

It provides the first detailed age and extinction estimates for clusters in Arp 284 using HST data, highlighting differences from other systems like the Antennae.

Findings

Clusters in NGC 7714 are mostly under 20 Myr old.

Bridge regions lack sufficient data for precise age estimates.

Older, unresolved stellar populations may exist in HII regions.

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$\alpha$ 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.