CEBAF at Jefferson Lab is striving to achieve its maximum reliability at the maximum deliverable energy for physics experiments. The most critical part of this is the acceleration systems in the two linacs. The individual limiting characteristics of the 3 20 srf cavities, each with its own klystron and control system, continue to be refined as is the system for providing optimal setup tools to operations. The field-emission-stimulated discharges at the cold rf waveguide input window continue as the energy- limiting effect. In addition, operation at increased rf power levels have produced unanticipated heating in the region near the warm polymeric rf windows. The latter has stimulated the migration to a more durable ceramic replacement window. During 2000, C EBAF encountered its first cryomodule helium leak into beam vacuum, most likely through an indium wire seal. Characterization of the leak and accommodation methods used will be described.

This work was supported by the U.S. DOE under contract DE-AC05-84ER40150.

Authors: C. Reece, J. Benesch, J. Preble

Abstract submitted to PAC 2001, Chicago, IL, June 18-24, 2001

Updated March 28, 2001

maintained by the Publications Manager