2 research outputs found
Analytical studies of Hawking radiation and quasinormal modes in rotating linear dilatonic black hole
The rotating linear dilatonic black hole is an asymptotically non-flat
solution to Einstein-Maxwell-Dilaton-Axion gravity theory due to the existence
of non-trivial matter fields. We have analytically studied the wave equation of
scalar field in this background and shown that the radial wave equation can be
solved in terms of hypergeometric function. By determining the ingoing and the
outgoing fluxes at the asymptotic infinity, we have found the analytical
expressions for reflection coefficient and greybody factor for certain scalar
modes. In the high frequency regime, we obtain the Hawking temperature by
comparing the blackbody spectrum with the radiation spectrum resulting from
reflection coefficient. It is shown that the Hawking temperature, which depends
only on the linear dilatonic background parameter, does not agree with the
temperature calculated from surface gravity. At last, the quasinormal modes of
scalar field perturbation are presented, which shows that the rotating linear
dilationic black hole is unstable for certain modes apart from the superradiant
modes.Comment: 7 pages, 2 figures Comments are welcom