Minimization of Longitudinal Emittance in Linear Accelerators

摘要

Linear accelerators (linacs) and linac-based lightsources are typically designed by manipulations in the longitudinal phase space. A minimal longitudinal emittance is considered as a quality factor of the particle bunch, where the phase space correlation, the peak current, the bunch energy and the charge distribution symmetry are represented as constraints in the design. A simulation tool capable of finding the optimal choice of parameters to achieve a minimum for the rms emittance under constraints is presented. A rough estimation of the global minimum using a Genetic Algorithm (GA) and a subsequent minimization using a Sequential Quadratic Programming (SQP) as hybrid configuration is proposed. First numerical results are presented.