The Clusters AgeS Experiment (CASE). Variable stars in the field of the open cluster NGC 6253

TL;DR

This study surveyed the open cluster NGC 6253, discovering 25 new variable stars, including eclipsing binaries and potential blue stragglers, providing new data to help determine the cluster's age and distance.

Contribution

It reports the discovery of 25 new variable stars in NGC 6253, including key systems for future detailed analysis, filling gaps from previous surveys.

Findings

25 new variable stars detected

Identification of candidate blue stragglers

New photometry data for 132 stars

Abstract

The field of the metal-rich open cluster NGC 6253 has been surveyed in a search for variable stars. A total of 25 new variables were detected, 14 of which are bright stars with 13<V<15 mag. This domain was not covered in an earlier work by de Marchi et al. (2010). Four variables, including three short-period eclipsing binaries, are candidate blue straggler stars. Two new detached eclipsing binaries at the turnoff of the cluster and another one on the subgiant branch were identified. These three systems deserve a detailed follow-up study aimed at a determination of the age and distance of NGC 6253. New photometry for 132 stars from the sample of de Marchi et al. (2010) is provided.