Hypervelocity Stars: From the Galactic Center to the Halo
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چکیده
Hypervelocity stars (HVS) traverse the Galaxy from the central black hole to the outer halo. We show that the Galactic potential within 200 pc acts as a high pass filter preventing low velocity HVS from reaching the halo. To trace the orbits of HVS throughout the Galaxy, we construct two forms of the potential which reasonably represent the observations in the range 5–10 pc, a simple spherically symmetric model and a bulge-disk-halo model. We use the Hills mechanism (disruption of binaries by the tidal field of the central black hole) to inject HVS into the Galaxy and compute the observable spatial and velocity distributions of HVS with masses in the range 0.6–4 M⊙. These distributions reflect the mass function in the Galactic Center, properties of binaries in the Galactic Center,
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تاریخ انتشار 2008