Research on barrier bucket voltage in synchrotron

Barrier bucket (BB) is used to enhance the intensity of the beam current by accumulation repeatedly in synchrotron. It can overcome the influence of space-charge effect. For realizing the beam accumulation repeatedly, it needs generating a single-sine voltage pulse in the accelerating cavity. Based on the single-sine waveforms characteristics, conditions and methods for generating barrier voltages are discussed in this paper. The bandwidth requirement of the signal is obtained according to the spectrum analysis of the signal, at the same time the relationship between the output voltage and the input excitation current is determined by using the method of equivalent parallel circuit and the linear time invariant approximation. The bandwidth requirement of the barrier RF signal is at least two times of the single sine frequency. The input excitation current is based on a single sinusoidal signal adding a DC pulse bias(the bias value equals to the Q value of cavity). Based on the results of the analysis, the BB voltage test was carried out on both of the ferrite loaded cavity of the cooling storage experimental ring (CSRe) and the newly developed magnetic alloy cavity,and the test results are discussed.