• ALOK DURGAPAL

Articles written in Journal of Astrophysics and Astronomy

• A search for variable stars in the four open star clusters

We present a CCD photometric survey for the search of variable stars in four open clusters namely Berkeley 69, King 5, King 7 and Berkeley 20. The time series observations were carried out for 1 and/or 2 nights for each of the clusters in the year 1998, which have led to identify nineteen variable stars in theseclusters. Out of these 19 variable stars, five stars show $\delta$ Scuti-like variability and two stars show W UMa type variability. In other stars, we could not find the periods, and hence the type of variability due to the lack of sufficient data. The periods of $\delta$ Scuti type stars are found to be in the range of 0.13–0.21 days, whereas the two stars in the cluster Berkeley 20, which showed W UMa type variability have orbital periods of 0.396 and 0.418 days, respectively. Using the Gaia data, the basic parameters of the clusters Berkeley 69, King 7 and King 5 are also revised. The age and reddening are estimated to be $0.79\pm 0.09$ Gyr and $0.68 \pm 0.03$ mag for Berkeley 69, $0.79\pm 0.09$ Gyr and $1.22 \pm 0.03$ mag for the cluster King 7 and $1.59\pm 0.19$ Gyr and $0.63\pm 0.02$ mag for the cluster King 5, respectively. The signature of mass segregation is found in the clusters King 7 and King 5.

• # Journal of Astrophysics and Astronomy

Volume 41, 2020
All articles
Continuous Article Publishing mode

• # Continuous Article Publication

Posted on January 27, 2016

Since January 2016, the Journal of Astrophysics and Astronomy has moved to Continuous Article Publishing (CAP) mode. This means that each accepted article is being published immediately online with DOI and article citation ID with starting page number 1. Articles are also visible in Web of Science immediately. All these have helped shorten the publication time and have improved the visibility of the articles.

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019