Thermal Radiation from a Fluctuating Event Horizon

We consider a pointlike two-level system undergoing uniformly accelerated motion. We evaluate the transition probability for a finite time interval of this system coupled to a massless scalar field near a fluctuating event horizon. Horizon fluctuations are modeled using a random noise which generates light-cone fluctuations. We study the case of centered, stationary and Gaussian random processes. The transition probability of the system is obtained from the positive-frequency Wightman function calculated to one loop order in the noise averaging process. Our results show that the fluctuating horizon modifies the thermal radiation but leaves unchanged the temperature associated with the acceleration.