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Proper motion and membership determination in the young open cluster NGC1662

W. S. Dias·R. Boczko·J. I. B. Camargo·R. Teixeira·P. Benevides-Soares
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Abstract

Relative proper motions and cluster membership probabilities of 30 stars within an area of 14' of diameter centered in the open cluster NGC1662 (α=04^{\rm h}48^{\rm m}, δ=+10^{\rm o}56') are determined by combining positions of stars observed by the Valinhos CCD meridian circle with those from other astrometric catalogues. Our basic source for first epoch of stars brighter than B=13 magnitudes is the AC2000 Catalogue, which provides a time baseline of about 90 years, whereas the USNO-A2.0 Catalogue is used for fainter stars, providing a time baseline of about 40 years in this region. Average accuracies in proper motion of 2 mas/yr and 7 mas/yr are achieved, respectively, when the AC2000 or the USNO-A2.0 is used. Membership determination is obtained by applying the Zhao & He (1990) method. The cluster proper motion was found to be (-3.2\pm 0.6) mas/yr in right ascension and (-1.6\pm 0.6) mas/yr in declination.

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W. S. Dias, R. Boczko, J. I. B. Camargo, R. Teixeira, P. Benevides-Soares. 2000-03-29. Proper motion and membership determination in the young open cluster NGC1662. https://arxiv.org/abs/astro-ph/0003440

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