Black holes in string-generated gravity models

Spherically symmetric solutions of d-dimensional Einstein-Maxwell theory with a Gauss-Bonnet term are classified. All spherically symmetric solutions of d-dimensional Einstein gravity coupled to the Gauss-Bonnet and Born-Infeld terms are derived, classified, and compared with the previous solutions. Thermodynamic properties of the black holes are discussed and the black-hole temperatures derived. Unlike the solutions of Einstein-Maxwell theory the solutions with a Born-Infeld term do not appear to have a stable end point with regard to thermal evaporation.