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CURious Variables Experiment (CURVE). CCD Photometry and Variable Stars in the field of open cluster NGC 637

P. Pietrukowicz·A. Olech·M. Wisniewski·P. Kedzierski·K. Mularczyk·K. Zloczewski·S. Starczewski·K. Szaruga
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Abstract

We present VI photometry for the open cluster NGC 637 which is located in the Cassiopeia region. Morphology of cluster color-magnitude diagram indicates that it is a young object with age of a few million years. The apparent distance modulus of the cluster is 13.9<(m-M)_V<14.3, while reddening is 0.69<E(V-I)<0.73. We estimated the heliocentric distance as 2.6<d<3.3 kpc. We also report the identification of two variable stars in NGC 637. One of the variables is a non-radial pulsating beta Cep-type star. Other one is a likely ellipsoidal variable, however its pulsating nature can not be excluded.

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P. Pietrukowicz, A. Olech, M. Wisniewski, P. Kedzierski, K. Mularczyk, K. Zloczewski, S. Starczewski, K. Szaruga. 2006-09-06. CURious Variables Experiment (CURVE). CCD Photometry and Variable Stars in the field of open cluster NGC 637. https://arxiv.org/abs/astro-ph/0609155

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