Development of multi-function emission module in LIAPIC3D code

To set emittance, velocity spread and beam tilt correctly, a multi-function emission module is developed in LIAPIC3D code. This module development is based on beam emission module, which could set beam energy, beam length correctly. During experiment, researchers could get value and angle of emittance. When setting emittance, researchers must input these two parameters. To set velocity spread, a Gauss random function is created. This function could create Gauss distribution random values, and which are related to particle energy. Beam tilt direction is determined by two angle parameters. After development of multi-function emission module, a proof principle simulation is designed. Emittance in different direction, velocity spread in z direction, and beam tilt are tested in simulation. The simulation results are coincident with input values, verifying the development of the multi-function module.