The planned upgrade of the CEBAF electron accelerator includes the development of an improved cryomodule. Several components differ substantially from the original CEBAF cryomodule; these include: the new 7-cell, 1.5 GHz cavities with integral helium vess el, a new, backlash-free cavity tuner, the waveguide coupler with its room-temperature ceramic window, and the HOM damping filters. In order to test the design features and performance of the new components, a horizontal cryostat (Horizontal Test Bed) has been constructed which allows testing with a turn around time of less than three weeks. This cryostat provides the environment for testing one or two cavities, with associated auxiliary components, in a condition similar to that of a real cryomodule. A s eries of tests has been performed on a prototype 7-cell cavity and the above-mentioned systems. In this paper the results of the tests on the cryostat, on the cavity performance, on its coupler, on the tuner characteristics, and on the microphonics behavi or will be reported.

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

Authors: I.E. Campisi, B. Carpenter, G.K. Davis, J. Delayen, M. Drury, E. Feldl, J. Fischer, A. Guerra, P. Kneisel, T. Hiatt, C. Hovater, K. Macha, J. Mammosser, V. Nguyen, L. Phillips, J. Preble

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

Updated March 28, 2001

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