Year: 2025
Type: article
Abstract: ABSTRACT We investigate the young stellar cluster population of M51 and how it is affected by encounters with giant molecular clouds (GMCs). We combine a galactic model with N-body simulations of 5000 unique clusters in the mass range $[600\!-\!24000]$ $\mathrm{M}_{\odot }$. We simulate each cluster twice: with (C$_{\rm {R}}$) and without (C$_{\rm {N}}$) tidal perturbations from the GMCs. We are able to reproduce the majority of the observed mass- and age functions. However, for the age function, we see a large discrepancy for clusters with masses $\sim$5000 $\mathrm{M}_{\odot }$, which is likely related to incompleteness in the observations. We find that old low-mass clusters, located close to the galactic centre, are most likely to be disrupted. The effect of GMC encounters causes a decrease in survivability by 8 per cent points for the oldest clusters with initial masses below 6000 $\mathrm{M}_{\odot }$. For 15 clusters, we find that the presence of GMCs can protect the C$_{\rm {R}}$ clusters from the rest of the galactic tidal field and thereby cause them to retain a significantly higher fraction of stars compared to the C$_{\rm {N}}$ clusters. For clusters that are supervirialized, we find that the C$_{\rm {R}}$ clusters have a higher virial ratio compared to the C$_{\rm {N}}$ clusters, which is a result of interactions with GMCs. We see no significant difference between the C$_{\rm {R}}$ and C$_{\rm {N}}$ populations, indicating that over a time period of 200 Myr the effect of the GMCs cannot be detected.
Authors: Timmi G Jørgensen, Ross P Church
Institution: Lund University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Funder: Lunds Universitet
OpenAlex ID: W4414364952