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arXiv · 1809.08275

On-Axis scalar absorption cross section of Kerr-Newman black holes: Geodesic analysis, sinc and low-frequency approximations

Carolina L. Benone·Luiz C. S. Leite·LuÍs C. B. Crispino·Sam R. Dolan
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Abstract

We investigate null geodesics impinging parallel to the rotation axis of a Kerr-Newman black hole, and show that the absorption cross section for a massless scalar field in the eikonal limit can be described in terms of the photon orbit parameters. We compare our sinc and low-frequency approximations with numerical results, showing that they are in excellent agreement.

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Carolina L. Benone, Luiz C. S. Leite, LuÍs C. B. Crispino, Sam R. Dolan. 2018-09-21. On-Axis scalar absorption cross section of Kerr-Newman black holes: Geodesic analysis, sinc and low-frequency approximations. https://doi.org/10.1142/s0218271818430125

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