Stochasticity effects on derivation of physical parameters of unresolved star clusters

TL;DR

This paper introduces a rapid modeling method for unresolved star clusters' broad-band magnitudes to accurately derive their physical parameters, validated on M33 galaxy clusters, showing minimal age-extinction degeneracy.

Contribution

A novel fast modeling approach for unresolved star clusters' magnitudes, enabling reliable estimation of age, mass, and extinction, validated against resolved stellar data.

Findings

Method accurately derives cluster parameters from unresolved data.

Results show minimal age-extinction degeneracy in M33 clusters.

Validated method against resolved stellar photometry.

Abstract

We developed a method for a fast modeling of broad-band UBVRI integrated magnitudes of unresolved star clusters and used it to derive their physical parameters (age, mass, and extinction). The method was applied on M33 galaxy cluster sample and consistency of ages and masses derived from unresolved observations with the values derived from resolved stellar photometry was demonstrated. We found that interstellar extinction causes minor age-extinction degeneracy for the studied sample due to a narrow extinction range in M33.