CLASSE, Ithaca, New York
The Cornell Energy Recovery Linac (ERL) Injector cryomodule is part of a prototype electron beam source to demonstrate production of CW 1.3 GHz, 100 mA average current, 2 ps, 77 pC bunches with emittance of 1 mm-mrad. After a successful initial run of the cryomodule with beam, an improvement program was initiated in the Fall 2009. The goals of the reconfiguration were to replace the RF absorbers in the beamline HOM loads that were subject to static charging, re-process the SRF cavities that exhibited a low Q that further decreased by 50% during the run, and improve diagnostic sensor accuracy within the cryomodule. The upgraded cryomodule was re-commissioned in early 2010 with excellent performance. Details of the investigation and remedies for HOM load charging, cavity Q recovery, and module assembly logistics will be presented along with the ERL Injector beam performance.
CLASSE, Ithaca, New York
This paper discusses the baseline superconducting RF cavity design to be used in Cornell's Energy Recovery Linac, a next generation light source. We discuss the methods used to obtain the design and present the cavity's figures of merit. The baseline cavity design is ready for prototyping, which will begin in the fall of 2010. Finally, we introduce small variations in the center cell design to increase the threshold current through the cavity by increasing the higher order mode relative frequency spread in the main linac, that have the effect of more than doubling the threshold current to 450 mA.