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arXiv · 0809.2692

Proper motions with Subaru I. Methods and a first sample in the Subaru Deep Field

Michael W. Richmond·Tomoki Morokuma·Mamoru Doi·Yutaka Komiyama·Naoki Yasuda·Sadanori Okamura·Avishay Gal-Yam
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Abstract

We search for stars with proper motions in a set of twenty deep Subaru images, covering about 0.28 square degrees to a depth of i ~ 25, taken over a span of six years. In this paper, we describe in detail our reduction and techniques to identify moving objects. We present a first sample of 99 stars with motions of high significance, and discuss briefly the populations from which they are likely drawn. Based on photometry and motions alone, we expect that 9 of the candidates may be white dwarfs. We also find a group of stars which may be extremely metal-poor subdwarfs in the halo.

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Michael W. Richmond, Tomoki Morokuma, Mamoru Doi, Yutaka Komiyama, Naoki Yasuda, Sadanori Okamura, Avishay Gal-Yam. 2008-09-16. Proper motions with Subaru I. Methods and a first sample in the Subaru Deep Field. https://doi.org/10.1093/pasj%2F61.1.97

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