Energy Recovery Linear Accelerator Lattice Design and Coherent Synchrotron Radiation
Energy Recovery Linear Accelerators (ERLs) are potential drivers for novel fourth-generation synchrotron light sources. An ERL combines the high quality beams of a linear accelerator with the high currents possible in a storage ring. The excessive power needs of a lone linac are avoided by circulating accelerated particles back through the linac to recover their energy. This dissertation is focused on the lattice design of a high energy ERL synchrotron light source at Cornell University. In order to illustrate general ERL requirements, a simpler design is also presented. The mathematics needed to describe such a machine are particular to accelerator physics, and so a separate chapter is devoted to developing all of the relevant concepts. The short bunch lengths and high bunch charges possible in an ERL can give rise to Coherent Synchrotron Radiation (CSR) which can potentially limit the operation of the accelerator. CSR is a collective phenomenon where the energy radiated at wavelengths longer than the bunch length is enhanced by the number of charges in the bunch. The final chapter develops an exact model for CSR from an infinitely thin bunch. It reveals many interesting effects, including CSR at low energies, through multiple bends in a lattice, and in bunch compression. The model is also used to obtain the limits of validity of previously known approximations. Finally, CSR is examined for the ERL designs presented.
dissertation or thesis