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arXiv · 1606.04792

A study of variable stars in the open cluster NGC 1582 and its surrounding field

Fang-Fang Song·Ali Esamdin·Lu Ma·Jin-Zhong Liu·Yu Zhang·Hu-Biao Niu·Tao-Zhi Yang
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Abstract

This paper presents the Charge-Coupled Device time-series photometric observations of the open cluster NGC 1582 and its surrounding field with Johnson B, V and R filters by using Nanshan 1m telescope of Xinjiang Astronomical Observatory. 19 variable stars and 3 variable candidates were detected in a 45 {\times} 48.75 field around the cluster. 12 of the variable stars are newly-discovered variable objects. The physical properties, classifications, and membership of the 22 objects are studied through their light curves, their positions on the color-magnitude diagram, and with the archival data from the Naval Observatory Merged Astrometric Dataset. Among these objects, 5 are eclipsing binary systems, 6 are pulsating variable stars including one known Delta Scuti star and one newly-discovered RR Lyrae star. The distance of the RR Lyrae star is estimated to be 7.9 {\pm} 0.3 kpc, indicates that the star locates far behind the cluster. 4 variable stars are probable members of the cluster, and 13 of the 22 objects are confirmed to be field stars.

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Fang-Fang Song, Ali Esamdin, Lu Ma, Jin-Zhong Liu, Yu Zhang, Hu-Biao Niu, Tao-Zhi Yang. 2016-06-15. A study of variable stars in the open cluster NGC 1582 and its surrounding field. https://doi.org/10.1088/1674-4527/16/10/154

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