title: Photon neutralizer as an example of an open billiard.
abstract: A simple photon cavity consisting of three flat mirrors is considered, which provides a model for a photon neutralizer of negative ion beams to be used in a neutral beam injector for plasma heating in fusion devices. Treating the system as an open mathematical billiard, the mechanism of photon scattering on the sharp boundary between two mirrors is described. Assuming a balance between the continuous injection of the photons into the device and their loss through its open ends, the stationary angular distribution of the photons in the trap is computed in closed form and an estimate for the confinement time of the photons in the neutralizer is provided.
authors: Budker Institute of Nuclear Physics, Lavrentyev Av. 11, Novosibirsk, 630090, Russia and Novosibirsk State University, Pirogov Str. 2, Novosibirsk, 630090, Russia. i.a.kotelnikov@inp.nsk.su
authors: I A
authors: IA
authors: Kotelnikov
authors: S S
authors: SS
authors: Popov
authors: M
authors: M
authors: Romé
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007909:Lenses; D008962:Models, Theoretical; D017785:Photons; D012031:Refractometry / Q000295:instrumentation*; D012542:Scattering, Radiation