The age sequence of young clusters in Perseus: Estimating ages from mass distributions

TL;DR

This study introduces a new method for estimating the ages of young star clusters based on their mass distributions, validated on six clusters in Perseus, and aligns well with existing age indicators.

Contribution

The paper presents a novel approach to determine cluster ages by comparing mass distributions, assuming a universal initial mass function, and applies it to six clusters in Perseus.

Findings

Age sequence established for six clusters from 1 to 8 Myr.

Method results are consistent with disc fraction and isochrone fitting.

Provides a complementary technique for age estimation in young clusters.

Abstract

Establishing ages for young clusters is key for properly tracking the star formation history of a region. In this paper we investigate a new approach to estimating ages for young populations, based on the well-founded assumption that the initial mass function is the same throughout a star forming cloud. We trial this method for six young clusters in the Perseus star forming region. For all six clusters, we construct new member samples in a homogeneous way using Gaia DR3. We estimate masses by comparing 2MASS photometry to theoretical isochrones, including Monte Carlo simulations to propagate the errors. We compare the mass distributions of the clusters for a range of plausible ages, looking for a combination of ages that results in indistinguishable mass distributions across the region. We find the best fit for ages of 1 Myr for NGC1333+Autochthe, 2 Myr for IC348, 2-3 Myr for Heleus, 3-4 Myr for Mestor, 4-5 Myr for Electryon+Cynurus, and 5-8 Myr for Alcaeus. All other combinations of ages are ruled out by this criterion. The established age sequence is consistent with the relative ages inferred from disc fractions, and broadly aligns with the age sequence determined in previous studies using isochrone fitting. We suggest that this approach can be a useful complement and cross-check to established methods to estimate ages in young populations.