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arXiv · 1405.7710

Predicted Space Motions for Hypervelocity and Runaway Stars: Proper Motions and Radial Velocities for the GAIA Era

Scott J. Kenyon·Benjamin C. Bromley·Warren R. Brown·Margaret J. Geller
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Abstract

We predict the distinctive three dimensional space motions of hypervelocity stars (HVSs) and runaway stars moving in a realistic Galactic potential. For nearby stars with distances less than 10~kpc, unbound stars are rare; proper motions alone rarely isolate bound HVSs and runaways from indigenous halo stars. At large distances of 20-100 kpc, unbound HVSs are much more common than runaways; radial velocities easily distinguish both from indigenous halo stars. Comparisons of the predictions with existing observations are encouraging. Although the models fail to match observations of solar-type HVS candidates from SEGUE, they agree well with data for B-type HVS and runaways from other surveys. Complete samples of g <= 20 stars with GAIA should provide clear tests of formation models for HVSs and runaways and will enable accurate probes of the shape of the Galactic potential.

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Scott J. Kenyon, Benjamin C. Bromley, Warren R. Brown, Margaret J. Geller. 2014-05-29. Predicted Space Motions for Hypervelocity and Runaway Stars: Proper Motions and Radial Velocities for the GAIA Era. https://doi.org/10.1088/0004-637x/793/2/122

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