• F.A. Laham
  Cornell University, Ithaca, New York
• G.H. Hoffstaetter, C.E. Mayes, J.R. Thompson
  CLASSE, Ithaca, New York

The proposed Cornell Energy Recovery Linac (ERL) is designed for bunches of 77pC and 100mA whose energy is recovered. However, the ERL linac can also be used for larger bunch charges of reduced average current whose energy does not have to be recovered. The proposed Cornell ERL lightsource currently uses a split linac arrangement connected by a turnaround arc. In order to avoid the detrimental effects of Coherent Synchrotron Radiation (CSR) in this arc, a high charge (1nC) bunch must remain relatively long (2ps), and be compressed at high energy (5GeV). An appropriate bunch compressor must take second order effects into account, which adds complications for the large energy spread associated with compression to 100fs or less. We have therefore designed a very simple four dipole bunch compressor at high energy, which uses second order time of flight terms in the turnaround arc rather than in the bunch compressor itself. This design is tested using particle tracking simulations incorporating CSR, as well as magnetic field errors and misalignments.