Effect of the long solenoid tunnel on the growth of emittance in the PNC high power electron linac

We developed a new, three-dimensional simulation code ETRA3D to calculate beam dynamics in the injector of PNC, high-power, high-duty electron linac. In ETRA3D, beam dynamics are calculated by Hamiltonian equations and the space-charge force is calculated by the potentials produced by other electrons. The Hamiltonian is calculated at each time step and the length of the time step is varied by a change in the Hamiltonian to reduce the error of transition and the calculation time. The precision of ETRA3D was checked by comparing it with the envelope equation. The agreement between them was good. We demonstrated the capabilities of ETRA3D by an example in which the electron beam is not launched along the axis of the series of the solenoid coils. Under this condition, two-dimensional codes can not calculate the beam dynamics