Effect of proper eddy fields on the beam characteristics in an accelerator with spatial-uniform focusing

The effect of proper curl fields on proton beam characteristics in a linear accelerator with spatial-uniform focusing in one-mode approximation without automatic control system is studied. The beam interacts with the field in the near axis region between electrodes. Field distortion in the resonator at the expense of operating oscillation excitation by the beam was considered. It is shown, that when 50 mA beam was accelerated, potential on the electrodes decreased from 122 kV to 95 kV. At that, capture coefficient for HF buncher decreased from 98% to 30%. The proper curl component of the beam field affects considerably the radial motion. With the current change from 5 mA to 50 mA the emittance increased in both planes by approximately 30%. Conclusions are made, that either conventional method - input of extra power at the moment of the beam acceleration, or a decrease in the rate of the accelerator synchronous phase change can be used to maintain a high capture coefficient