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arXiv · 1707.01144

Absorption of electromagnetic and gravitational waves by Kerr black holes: Shadows, superradiance and the spin-helicity effect

Luiz C S Leite·Sam R Dolan·Luís C B Crispino
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Abstract

We study the absorption of plane waves by Kerr black holes. We calculate the absorption cross section: the area of the black hole shadow at a finite wavelength. We present a unified picture of the absorption of all massless bosonic fields, focussing on the on-axis incidence case. We investigate the spin-helicity effect, arising from a coupling between dragging of frames and the helicity of a polarized wave. We introduce and calibrate an extended sinc approximation which provides new quantitative data on the spin-helicity effect in strong-field gravity.

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Luiz C S Leite, Sam R Dolan, Luís C B Crispino. 2017-07-04. Absorption of electromagnetic and gravitational waves by Kerr black holes: Shadows, superradiance and the spin-helicity effect. https://doi.org/10.1016/j.physletb.2017.09.048

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