Age and mass constraints for a young massive cluster in M31 based on spectral-energy-distribution fitting

TL;DR

This study estimates the age and mass of the young massive star cluster VDB0-B195D in M31 using spectral-energy-distribution fitting across multiple photometric bands, confirming its youth and massiveness.

Contribution

It introduces a comprehensive SED fitting method combining BATC, optical, and near-infrared data to accurately determine the cluster's age and mass.

Findings

Age estimated at 60.0±8.0 Myr

Mass estimated between 1.1 and 1.6 x 10^5 solar masses

Confirmed VDB0-B195D as a young massive cluster in M31

Abstract

VDB0-B195D is a massive, blue star cluster in M31. It was observed as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey using 15 intermediate-band filters covering a wavelength range of 3000--10,000 \AA. Based on aperture photometry, we obtain its spectral-energy distribution (SED) as defined by the 15 BATC filters. We apply previously established relations between the BATC intermediate-band and the Johnson-Cousins $UBVRI$ broad-band systems to convert our BATC photometry to the standard system. A detailed comparison shows that our newly derived $VRI$ magnitudes are fully consistent with previous results, while our new $B$ magnitude agrees to within $2\sigma$. In addition, we determine the cluster's age and mass by comparing its SED (from 3000 to 20,000{\AA}, comprising photometric data in the 15 BATC intermediate bands, optical broad-band $BVRI$, and 2MASS near-infrared $JHK_{\rm s}$ data) with theoretical stellar population synthesis models, resulting in age and mass determinations of $60.0\pm 8.0$~Myr and $(1.1-1.6) \times 10^5 M_\odot$, respectively. This age and mass confirms previous suggestions that VDB0-B195D is a young massive cluster in M31.