uvby beta photoelectric photometry of the open cluster NGC 6823

Abstract

Absolute uvbybeta photoelectric photometry of the brightest stars in the direction of the Open Cluster NGC 6823 has been secured and is presented. From the data analysis, reddening, distance, temperature and gravity are determined for the B, A, F stars and, from these, reddening and a mean distance modulus (12.475 +/- 0.414 mag) to the cluster are determined. Also, their membership in the cluster has been established and a numerical value of the age is determined through direct comparison with theoretical models. A brief analysis of the short period variable stars in the direction of NGC 6823 is made. We have concluded that they might not be pre-MS delta Scuti stars.