Four-vane HF quadrupole resonant cavity for particle acceleration

摘要

A four-vane HF quadrupole mode resonant cavity for the acceleration of low-energy electrically charged particles comprises two pairs of solid metal vanes (4) positioned mutually at right angles (XY,YZ) within an evacuated tank (not shown) and cooled by a circulating fluid. Each pair of vanes supports a silver or copper plated ring (2,3) concentrically aligned with the axis of particle travel (Z) and axially spaced to present a vane-to-vane short circuit dimensionally related to the resonant frequency of the system and particle speed, in order to obviate dipole mode effects. The construction offers three successive acceleration gaps (6,7,8) and does not require direct cooling of the rings (2,3) or their supports.