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arXiv · 1501.07824

Nearby Low-Mass Hypervelocity Stars

Yanqiong Zhang·Martin C. Smith·Jeffrey L. Carlin
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Abstract

Hypervelocity stars are those that have speeds exceeding the escape speed and are hence unbound from the Milky Way. We investigate a sample of low-mass hypervelocity candidates obtained using data from the high-precision SDSS Stripe 82 catalogue, which we have combined with spectroscopy from the 200-inch Hale Telescope at Palomar Observatory. We find four good candidates, but without metallicities it is difficult to pin-down their distances and therefore total velocities. Our best candidate has a significant likelihood that it is escaping the Milky Way for a wide-range of metallicities.

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Yanqiong Zhang, Martin C. Smith, Jeffrey L. Carlin. 2015-01-30. Nearby Low-Mass Hypervelocity Stars. https://doi.org/10.1051/eas%2F1567046

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