Hawking radiation of asymptotically nonflat dyonic black holes in Einstein-Maxwell-dilaton gravity

In the present paper, we investigate the Hawking radiation of asymptotically nonflat dyonic black holes in 4D Einstein-Maxwell-dilaton gravity in semiclassical approximation. We show that the problem allows an exact analytical treatment and we compute exactly the semiclassical radiation spectrum of both nonextremal and extremal black holes under consideration. In the high-frequency regime, we find that the Hawking temperature does not agree with the surface gravity when the magnetic charge is nonzero. Even more surprisingly, the Hawking temperature is independent of the black hole intrinsic characteristics, as the mass and magnetic charge, and depends only on the linear dilaton background parameter.