Constraining star cluster disruption mechanisms

TL;DR

This paper investigates star cluster disruption mechanisms using M33 as a case study, revealing that observed age distributions are shaped by detection limits and suggesting a possible mass dependence in disruption processes.

Contribution

It demonstrates that the apparent power-law age distribution results from detection limits and explores models of cluster disruption considering observational biases and theoretical frameworks.

Findings

Age distribution follows a power law due to detection limits.

Mass cuts reveal a composite disruption structure.

Disruption processes may depend on cluster mass.

Abstract

Star clusters are found in all sorts of environments and their formation and evolution is inextricably linked to the star formation process. Their eventual destruction can result from a number of factors at different times, but the process can be investigated as a whole through the study of the cluster age distribution. Observations of populous cluster samples reveal a distribution following a power law of index approximately -1. In this work we use M33 as a test case to examine the age distribution of an archetypal cluster population and show that it is in fact the evolving shape of the mass detection limit that defines this trend. That is to say, any magnitude-limited sample will appear to follow a dN/dt=1/t, while cutting the sample according to mass gives rise to a composite structure, perhaps implying a dependence of the cluster disruption process on mass. In the context of this framework, we examine different models of cluster disruption from both theoretical and observational standpoints.