CERN Accelerating science

Article
Title	Overview of SNS Cryomodule Performance
Author(s)	Drury, Michael A ; Daly, Edward ; Davis, Kirk ; Delayen, Jean R ; Grenoble, Christiana ; Hicks, William R ; King, Larry ; Plawski, Tomasz ; Powers, Tom ; Preble, Joseph P ; Wang, Haipeng ; Wiseman, Mark
Affiliation	(Jefferson Lab, Newport News, Virginia)
Publication	2005
In:	21st IEEE Particle Accelerator Conference, Knoxville, TN, USA, 16 - 20 May 2005, pp.3496
Subject category	Accelerators and Storage Rings
Abstract	Thomas Jefferson National Accelerating Facility (Jefferson Lab) has completed production of 24 Superconducting Radio Frequency (SRF) cryomodules for the Spallation Neutron Source (SNS) superconducting linac. This includes one medium-beta (0.61) prototype, eleven medium-beta and twelve high-beta (0.81) production cryomodules. Ten medium-beta cryomodules as well as two high beta cryomodules have undergone complete operational performance testing in the Cryomodule Test Facility at Jefferson Lab. The set of tests includes measurements of maximum gradient, unloaded Q (Q0), microphonics, and response to Lorentz forces. The Qext's of the various couplers are measured and the behavior of the higher order mode couplers is examined. The mechanical and piezo tuners are also characterized. The results of these performance tests will be discussed in this paper.