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arXiv · 1704.03455

Hunting Black Holes with Gaia

Natalie Mashian·Abraham Loeb
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Abstract

We predict the number of black holes with stellar companions that are potentially detectable with Gaia astrometry over the course of its five-year mission. Our model estimates that nearly 2$\times$10$^5$ astrometric binaries hosting black holes and stellar companions brighter than Gaia's detection threshold, G $\sim$ 20, should be discovered with 5$\sigma$ sensitivity. Among these detectable binaries, systems with longer orbital periods are favored, and black hole and stellar companion masses in the range M$_{BH} \sim$ 6-10 M$_\odot$ and M$_* \sim$ 1-2 M$_\odot$, respectively, are expected to dominate.

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Natalie Mashian, Abraham Loeb. 2017-04-11. Hunting Black Holes with Gaia. https://doi.org/10.1093/mnras/stx1410

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