buncher
see also:
Pre-Buncher, Phase Buncher, RF Buncher, Radieofrequency Buncher, Velociy Modulator
A buncher is a radio-frequency cavity or resonator that groups or “bunches” ions or particles into compact, concentrated groups (bunches) as they travel in an ion beam. This helps to increase the density of the particles in certain sections of the beam, thus improving the efficiency of the ion acceleration or the interaction of the beam with a target material by focusing. Bunchers are frequently used in ion beam systems and particle accelerators.