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arXiv · 2112.12865

Absorption by stringy black holes

Sérgio Vinicius M. C. B. Xavier·Carolina L. Benone·Luís C. B. Crispino
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Abstract

We investigate the absorption of planar massless scalar waves by a charged rotating stringy black hole, namely a Kerr--Sen black hole. We compute numerically the absorption cross section and compare our results with those of the Kerr-Newman black hole, a classical general relativity solution. In order to better compare both charged black holes, we define the ratio of the black hole charge to the extreme charge as $Q$. We conclude that Kerr--Sen and Kerr-Newman black holes have a similar absorption cross section, with the difference increasing for higher values of $Q$.

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Sérgio Vinicius M. C. B. Xavier, Carolina L. Benone, Luís C. B. Crispino. 2021-12-23. Absorption by stringy black holes. https://doi.org/10.1140/epjc%2Fs10052-021-09933-9

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