Bunch Energy Loss in Cavities: Dependence on Beam Velocity
نویسنده
چکیده
Proton or H linacs accelerate particles through the wide range of the particle velocities. For intense beams, and especially when superconducting cavities are used, a detailed knowledge about how the beam energy loss depends on the beam velocity = v=c, and what part of the lost energy remains in the cavity, is required to calculate the cavity heat load. Using a frequency-domain approach, we calculate the bunch energy loss as a function of for a few particular cases. We are mostly concerned about the cavity modes below the beam-pipe cutoff, because they produce most of the cavity heating. While the loss factor due to an individual mode can show peaks at some particular values of , the total loss for important particular cases was found smoothly decreasing as decreases. Comparison with time-domain results for the ultra-relativistic case, ! 1, is also presented.
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