Beam Brightness Booster with Self-Stabilization of Electron-Proton Instability

The brightness and intensity of a circulating proton beam now can be increased up to space charge limit by means of charge exchange injection or by an electron cooling but cannot be increased above this limit. Significantly higher brightness can be produced by means of the charge exchange injection with the space charge compensation [1]. The brightness of the space charge compensated beam is limited at low level by development of the electron-proton (e-p) instability. Fortunately, e-p instability can be self-stabilized at a high beam density. Discovery of “cesiation effect” significantly increases the negative ion emission from gas discharges, and surfaceplasma sources for intense high brightness negative ion beams production were developed. These developments prepared a possibility for production of stable “superintense” circulating beam with intensity and brightness far above the space charge limit. A beam brightness booster (BBB) for significant increase of accumulated beam brightness is discussed. The superintense beam production can be simplified by developing of nonlinear nearly integrable focusing system with broad spread of betatron tune and the broadband feedback system for e-p instability suppression [2].