Evolution of the electron beam envelope in a free electron laser beamline

Abstract

The free electron laser (FEL) is a new generation of laser whose development motivates further research in basic and applied physics. Unlike a conventional laser that uses a gas or solid state gain medium, the FEL gain medium is a relativistic electron beam produced by a particle accelerator. This thesis will explore electron beam dynamics in an FEL, including the beam envelope equation, which will help us understand the evolution of electron betatron motion in the undulator. Dipole magnets, quadrupoles, and solenoids play important roles in transporting and focusing in an FEL beamline. The dipole magnets redirect the electron beam to a beam dump or recirculate the electrons for energy recovery. The quadrupoles and solenoids collimate and focus the electron beam. Simulations and theory are used to model and study a simple FEL beamline.