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arXiv · 1401.7932

On the Origin of Young Stars at the Galactic Center

Ann-Marie Madigan·Oliver Pfuhl·Yuri Levin·Stefan Gillessen·Reinhard Genzel·Hagai B. Perets
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Abstract

The center of our galaxy is home to a massive black hole, SgrA*, and a nuclear star cluster containing stellar populations of various ages. While the late type stars may be too old to have retained memory of their initial orbital configuration, and hence formation mechanism, the kinematics of the early type stars should reflect their original distribution. In this contribution we present a new statistic which uses directly-observable kinematical stellar data to infer orbital parameters for stellar populations, and is capable of distinguishing between different origin scenarios. We use it on a population of B-stars in the Galactic center that extends out to large radii (0.5 pc) from the massive black hole. We find that the high K-magnitude population form an eccentric distribution, suggestive of a Hills binary-disruption origin.

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Ann-Marie Madigan, Oliver Pfuhl, Yuri Levin, Stefan Gillessen, Reinhard Genzel, Hagai B. Perets. 2014-01-30. On the Origin of Young Stars at the Galactic Center. https://doi.org/10.1017/s1743921314000659

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