Free Energy and Emittance Growth Caused by Bunched Beam With Gaussian Distribution in Longitudinal Direction in Linac

摘要

正 The nonlinear space charge effect of bunched beam in linac is one of the important factors thatinduces the emittance growth due to the conversion of the field energy to kinetic energy.In this paper,us-ing a cylinder model of space charge in linac,we derived the internal energy for a bunched beam withsome nonuniform space charge distributions,such as longitudinal Gaussian distribution combined withKapchinskij-Vladimirski1,waterbag,parabolic or Gaussian transverse distribution.And the emittancegrowth caused by the above distributions is worked out.