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arXiv · 1505.02822

Basic Parameters of Open Star Clusters DOLIDZE 14 and NGC 110 in Infrared bands

Gireesh C. Joshi·Y. C. Joshi·S. Joshi·R. K. Tyagi
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Abstract

The basic physical parameters of a poorly studied open cluster NGC 110 and an unstudied open cluster DOLIDZE 14 are estimated in the present study using the archival PPMXL and WISE catalogues. The radius of both the clusters are estimated by fitting the modified King's empirical model on their stellar density profiles. The other basic parameters of the clusters such as distance, reddening, and age are obtained by visual fitting of the Marigo's solar metallicity isochrone on their IR colour-magnitude diagrams (CMDs). The mean-proper motion of the clusters are estimated through the individual proper motion of probable members identified through the dynamical and statistical methods. The archival catalogues (JHKW1W2) are constructed for both the clusters by compiling the extracted data from the PPMXL and WISE catalogues. The various colour-excesses, such as E(J-H), E(H-K) and E(W1-W2), are estimated using the best fit theoretical isochrone on the (J-H)-H, (H-K)-H and (W1-W2)-H CMDs, respectively. The ratios of various infrared colours of the clusters are obtained through their two-colour diagrams. We also identify the most probable members in these clusters by estimating spatial, kinematic and spatio-kinematic probabilities of stars within the cluster. A correlation between the E(H-K) and E(W1-W2) is also established.

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Gireesh C. Joshi, Y. C. Joshi, S. Joshi, R. K. Tyagi. 2015-05-11. Basic Parameters of Open Star Clusters DOLIDZE 14 and NGC 110 in Infrared bands. https://doi.org/10.1016/j.newast.2015.04.003

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