Improved proper motion determinations for 15 open clusters based on the UCAC4 catalog

TL;DR

This paper improves proper motion measurements for 15 nearby open clusters by applying photometric criteria and using UCAC4 data, highlighting the impact of contamination treatment on results.

Contribution

It introduces a new approach that emphasizes photometric criteria for more accurate proper motion determinations of open clusters.

Findings

Proper motions differ significantly from previous results.

Photometric criteria improve accuracy of cluster motion measurements.

Field star contamination significantly affects proper motion calculations.

Abstract

The proper motions of 15 nearby (d < 1 kpc) open clusters were recalculated using data from the UCAC4 catalog. Only evolved or main sequence stars inside a certain radius from the center of the cluster were used. The results differ significantly from the ones presented by Dias et al. (2014). This could be explained by the different approach to taking the field star contamination into account. The present work aims to emphasize the importance of applying photometric criteria for the calculation of open cluster proper motions.