An accelerator for charged particle may include: a capacitor stack which includes a first electrode that can be brought to a first potential, a second electrode that is concentric to the first electrode and can be brought to a second potential differing from the first potential, and at least one intermediate electrode that is concentrically arranged between the first electrode and the second electrode and can be brought to an intermediate potential lying between the first potential and the second potential; a switching device to which the electrodes of the capacitor stack are connected and which is designed such that the concentric electrodes of the capacitor stack can be brought to increasing potential stages during operation of the switching device; a first and a second acceleration channel formed by first and second openings in the electrodes of the capacitor stack such that charged particles can be accelerated along the first and second acceleration channel by means of the electrodes; and a device which can influence the accelerated particle beam within the capacitor stack such that photons emitted by the particle beam are produced.