Constraining Black Hole Spin based on the Absence of Lense-Thirring Precession of Megamaser Clumps

Santiago Giner; Abraham Loeb

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arXiv · 2104.05084

Constraining Black Hole Spin based on the Absence of Lense-Thirring Precession of Megamaser Clumps

Santiago Giner·Abraham Loeb

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Abstract

We make use of the absence of Lense-Thirring precession of the innermost megamaser clumps around black holes in order to place upper limits on the spin amplitude of seven black holes at the center of megamaser galaxies: NGC 4258, NGC 2273, UGC 3789, NGC 3393, NGC 5495, NGC 5765b, and UGC 6093. The constraints are derived by requiring that the associated precession time-scale be longer than the age of the megamaser clumps, in order to preserve the single-plane geometry of the megamasers.

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Santiago Giner, Abraham Loeb. 2021-04-11. Constraining Black Hole Spin based on the Absence of Lense-Thirring Precession of Megamaser Clumps. https://arxiv.org/abs/2104.05084

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