Young massive clusters in the interacting LIRG Arp 299: evidence for the
  dependence of star cluster formation and evolution on environment
  Archival WFC3/UVIS imaging of Arp 299 (NGC 3690E + NGC 3690W) is retrieved to
investigate the young massive cluster (YMC) population of this ongoing merger.
We extract 2182 cluster candidates, including 1323 high confidence photometric
sources. Multiband photometry is matched with Yggdrasil models to estimate the
age, mass, and extinction of each cluster. A Schechter fit of the truncated
cluster mass function results in a characteristic mass ${\rm M_{*} = 1.6 \times
10^6 M_{\odot}}$. Our results confirm that intensely star-forming galaxies such
as Arp 299 host more massive clusters than quiescent dwarf and normal spirals.
In the case of NGC 3690E, we find that the cluster masses decrease with an
increasing galactocentric radius likely due to the gas density distribution. On
the other hand, the fitted age distributions of a mass-limited sample suggest
that YMCs of the western component undergo stronger disruption than those
hosted by the eastern galaxy. This is in agreement with the properties of the
underlying cluster luminosity functions: a clear truncation at high
luminosities with slopes generally shallower by $\sim 0.3$ dex than the ones of
the NGC 3690E. Finally, the derived cluster formation efficiency, $\Gamma \sim
19$ percent, indicates that Arp 299 has $\sim 3-5$ times more star formation
happening in bound clusters compared to the cases of gas-poor spirals like NGC
2997 and NGC 4395. The merger generally follows the $\Gamma - $ star formation
rate density relation from the literature. The YMC photometric study of Arp 299
thus reveals that both formation and disruption mechanisms of the star cluster
population are most likely environment-dependent.
