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

Abstract

Dilatonic black hole dyon-like solutions in the gravitational $4d$ model with a scalar field, two 2-forms, two dilatonic coupling constants $\lambda_i \neq 0$, $i =1,2$, obeying $\lambda_1 \neq - \lambda_2$ and the sign parameter $\varepsilon = \pm 1$ for scalar field kinetic term are overviewed. Here $\varepsilon = - 1$ corresponds to a phantom scalar field. The solutions are defined up to solutions of two master equations for two moduli functions, when $\lambda^2_i \neq 1/2$ for $\varepsilon = - 1$. Several integrable cases corresponding to Lie algebras $A_1 + A_1$, $A_2$, $B_2 = C_2$ and $G_2$ are considered. Some physical parameters of the solutions are derived: gravitational mass, scalar charge, Hawking temperature, black hole area entropy and PPN parameters $\beta$ and $\gamma$. Bounds on the gravitational mass and scalar charge (based on a certain conjecture) are presented.