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arXiv · 2001.01729

Tidal effects and disruption in superradiant clouds: a numerical investigation

Vitor Cardoso·Francisco Duque·Taishi Ikeda
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Abstract

The existence of light, fundamental bosonic fields is an attractive possibility that can be tested via black hole observations. We study the effect of a tidal field -- caused by a companion star or black hole -- on the evolution of superradiant scalar-field states around spinning black holes. For small tidal fields, the superradiant "cloud" puffs up by transitioning to excited states and acquires a new spatial distribution through transitions to higher multipoles, establishing new equilibrium configurations.For large tidal fields the scalar condensates are disrupted; we determine numerically the critical tidal moments for this to happen and find good agreement with Newtonian estimates. We show that the impact of tides can be relevant for known black-hole systems such as the one at the center of our galaxy or the Cygnus X-1 system. The companion of Cygnus X-1, for example, will disrupt possible scalar structures around the BH for gravitational couplings as large as $M\mu\sim 2\times 10^{-3}$.

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Vitor Cardoso, Francisco Duque, Taishi Ikeda. 2020-01-06. Tidal effects and disruption in superradiant clouds: a numerical investigation. https://doi.org/10.1103/physrevd.101.064054

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