Behavior of space charge dominated beam during longitudinal compression in a bunching system

Longitudinal and transverse beam dynamics during the bunch compression in a beam bunching system have been studied using disc model and envelope equation. The major contribution here is the inclusion of the effect of axial variation of the longitudinal electric field in the space charge term of beam envelope equation. Also included is a random Gaussian energy spread in the beam before the compression begins. In addition, the emittance growth resulting from the time dependant rf field in the transverse direction has been taken into account and the effective value of beam emittance has been used in the beam envelope equation. Finally, we have studied the beam bunching system of 100 keV proton to be used in the injection line of the 10 MeV high current compact cyclotron. Various numerical results of the study are presented for different geometrical and beam parameters.