Basic parameters of three star clusters in the Small Magellanic Cloud: Kron 11, Kron 63 and NGC 121

TL;DR

This study analyzes three star clusters in the Small Magellanic Cloud, determining their structure and fundamental parameters, revealing age differences and mass segregation, and providing new insights into poorly studied clusters Kron 11 and Kron 63.

Contribution

First detailed study of Kron 11 and Kron 63, providing their fundamental parameters and age estimates, and confirming mass segregation in NGC 121.

Findings

NGC 121 is old with low metallicity and shows mass segregation.

Kron 11 is several gigayears younger than NGC 121.

Kron 63 is a very young star aggregate.

Abstract

We present observations for three star clusters, Kron 11, Kron 63 and NGC 121, in the Small Magellanic Cloud. We have studied their structure and derived their fundamental parameters by means of their luminosity functions, their color magnitude diagrams and the Padova suite of isochrones. NGC 121 is a well studied object, for which we confirm previous evidence about its old age and low metal content, and have found that it is undergoing mass segregation. Kron 11 and Kron 63 are poorly populated clusters which had never been studied so far. Kron 11 is several gigayears younger than NGC 121, while Kron 63 is basically a very young star aggregate. Both clusters are immersed in dense stellar fields which share the same population properties, suggesting that in their cases, cluster ages are consistent with typical ages of field stars.