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arXiv · 2102.12102

Absorption of massless scalar field by furry black holes in de Rham-Gabadadze-Tolley theory

Abstract

We study the absorption of massless scalar field by two types furry charged black holes in de Rham-Gabadadze-Tolley (dRGT) theory. The absorption cross section is calculated in high frequency limit $\sigma_{hf}$ and low frequency limit $\sigma_{lf}$. We show that the high frequency limit $\sigma_{hf}$ is the area of shadow and the low frequency limit $\sigma_{lf}$ is the area of horizon. The ratio $R_{f}=\frac{\sigma_{hf}}{\sigma_{lf}}$ is used to measure the impact of charges on the absorption spectra of furry black hole. If the black hole possess an extra charge except mass, the interval value of absorption ratio $R_{f}$ is different: $[1,\frac{27}{16}]$ for electric charge, $[0.7675,\frac{27}{16}]$ for positive charge and $[\frac{27}{16},3.1835]$ for negative charge. We also use a numerical method to compute the absorption cross section in the finite frequency domain. A series of numerical results are presented.

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Ping Li, Yang Huang, Xin-Zhou Li. 2021-02-24. Absorption of massless scalar field by furry black holes in de Rham-Gabadadze-Tolley theory. https://arxiv.org/abs/2102.12102

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