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arXiv · 1701.02029

Dilatonic dyon-like black hole solutions in the model with two Abelian gauge fields

M. E. Abishev·K. A. Boshkayev·V. D. Ivashchuk
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Abstract

Dilatonic black hole dyon-like solutions in the gravitational $4d$ model with a scalar field, two 2-forms, two dilatonic coupling constants $λ_i \neq 0$, $i =1,2$, obeying $λ_1 \neq - λ_2$ and the sign parameter $\varepsilon = \pm 1$ for scalar field kinetic term are considered. Here $\varepsilon = - 1$ corresponds to a ghost scalar field. These solutions are defined up to solutions of two master equations for two moduli functions, when $λ^2_i \neq 1/2$ for $\varepsilon = - 1$. Some physical parameters of the solutions are obtained: gravitational mass, scalar charge, Hawking temperature, black hole area entropy and parametrized post-Newtonian (PPN) parameters $β$ and $γ$. The PPN parameters do not depend on the couplings $λ_i$ and $\varepsilon$. A set of bounds on the gravitational mass and scalar charge are found by using a certain conjecture on the parameters of solutions, when $1 +2 λ_i^2 \varepsilon > 0$, $i =1,2$.

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M. E. Abishev, K. A. Boshkayev, V. D. Ivashchuk. 2017-03-24. Dilatonic dyon-like black hole solutions in the model with two Abelian gauge fields. https://doi.org/10.1140/epjc%2Fs10052-017-4749-1

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