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arXiv · 1511.02634

Superradiance in static black hole spacetimes

Carolina L. Benone·Luís C. B. Crispino
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Abstract

We investigate the absorption of a massive and charged scalar field in a Reissner-Nordström background. We compare our numerical results for the absorption cross section, obtained for arbitrary frequencies, with the low- and high-frequency limits. We find, in particular, that the total absorption cross section can be negative, showing that planar scalar waves can be superradiantly amplified by black holes.

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Carolina L. Benone, Luís C. B. Crispino. 2015-11-09. Superradiance in static black hole spacetimes. https://doi.org/10.1103/physrevd.93.024028

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