Analytical study of greybody factor and quasinormal modes for the scalar field in rotating linear dilaton black hole

The rotating linear dilaton 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. We further apply the method of Damour–Ruffini to investigate the Hawking radiation of the rotating linear dilaton black hole, which shows that the Hawking temperature is proportional to the surface gravity of event horizon. Finally, the quasinormal modes of scalar field perturbation are also presented, which shows that the rotating linear dilation black hole is unstable for certain modes apart from the superradiant modes