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arXiv · hep-th/9704199

Absorption of fixed scalar in scattering off 4D N=4 black holes

H. W. Lee·Y. S. Myung·Jin Young Kim
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Abstract

We perform the perturbation analysis of the black holes in the 4D, N=4 supergravity. Analysis around the black holes reveals a complicated mixing between the dilaton and other fields (metric and two U(1) Maxwell fields). It turns out that considering both s-wave (l=0) and higher momentum modes (l \neq 0), the dilaton as a fixed scalar is the only propagating mode with $P=Q, h_1=h_2=0$ and $F = -G = 2ϕ$. We calculate the absorption cross-section for scattering of low frequency waves of fixed scalar and U(1) Maxwell fields off the extremal black hole.

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H. W. Lee, Y. S. Myung, Jin Young Kim. 1997-06-02. Absorption of fixed scalar in scattering off 4D N=4 black holes. https://doi.org/10.1016/s0370-2693(97)00794-6

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