Wakefield Calculations for 3 D Collimators ∗
نویسنده
چکیده
Using a recently developed time domain numerical approach we calculate the short-range geometric wakefields of 3D collimators and compare with analytical models. We find, in the diffractive regime, that the transverse mode kick factor can be approximated from the change in field energy between the beam pipe and the collimator if the collimator is long, or using a “field clipping” estimate if it is short. For collimators of past and present measurements at SLAC, numerical, analytical, and measurement results are compared.
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