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arXiv · hep-th/0701288

Greybody Factors for Brane Scalar Fields in a Rotating Black-Hole Background

S. Creek·O. Efthimiou·P. Kanti·K. Tamvakis
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Abstract

We study the evaporation of (4+n)-dimensional rotating black holes into scalar degrees of freedom on the brane. We calculate the corresponding absorption probabilities and cross-sections obtaining analytic solutions in the low-energy regime, and compare the derived analytic expressions to numerical results, with very good agreement. We then consider the high-energy regime, construct an analytic high-energy solution to the scalar-field equation by employing a new method, and calculate the absorption probability and cross-section for this energy regime, finding again a very good agreement with the exact numerical results. We also determine the high-energy asymptotic value of the total cross-section, and compare it to the analytic results derived from the application of the geometrical optics limit.

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S. Creek, O. Efthimiou, P. Kanti, K. Tamvakis. 2007-05-03. Greybody Factors for Brane Scalar Fields in a Rotating Black-Hole Background. https://doi.org/10.1103/physrevd.75.084043

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