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arXiv · 2010.02214

Observable Signatures of the Ejection Speed of Interstellar Objects from their Birth Systems

Amir Siraj·Abraham Loeb
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Abstract

`Oumuamua and Borisov were the first two interstellar objects confirmed in the Solar system. The upcoming commencement of the Vera C. Rubin Observatory's Legacy Survey of Space of Time (LSST) will enhance greatly the discovery rate of interstellar objects. This raises the question, what can be learned from large-number statistics of interstellar objects? Here, we show that discovery statistics provided by LSST will allow low- and high-ejection-speed populations to be distinguished using the velocity dispersion and angular anisotropy of interstellar objects. These findings can be combined with physical characterizations to yield a better understanding of planetary system origin and nature.

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Amir Siraj, Abraham Loeb. 2020-10-05. Observable Signatures of the Ejection Speed of Interstellar Objects from their Birth Systems. https://doi.org/10.3847/2041-8213%2Fabc170

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