skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: SNS Cryogenic Systems Commissioning

Abstract

The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K cold box (consisting of 4 stages of cold compressors), gaseous helium storage, helium purification and gas impurity monitoring system, liquid nitrogen storage and the cryogenic distribution transfer line system. The overall system commissioning and future plans will be presented.

Authors:
; ; ; ; ; ;  [1]; ; ; ; ;  [2]
  1. SNS Project, Oak Ridge National Laboratory, Tennessee, 37831 (United States)
  2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, Virginia, 23606 (United States)
Publication Date:
OSTI Identifier:
20800204
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 823; Journal Issue: 1; Conference: Cryogenic engineering conference, Keystone, CO (United States), 29 Aug - 2 Sep 2005; Other Information: DOI: 10.1063/1.2202566; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 43 PARTICLE ACCELERATORS; CAVITY RESONATORS; COMMISSIONING; COMPRESSORS; CRYOGENICS; DISTRIBUTION; HELIUM; LINEAR ACCELERATORS; LIQUIDS; NEUTRON SOURCES; NITROGEN; ORNL; RADIOWAVE RADIATION; REFRIGERATION; SPALLATION

Citation Formats

Hatfield, D., Casagrande, F., Campisi, I., Gurd, P., Howell, M., Stout, D., Strong, H., Arenius, D., Creel, J., Dixon, K., Ganni, V., and Knudsen, P. SNS Cryogenic Systems Commissioning. United States: N. p., 2006. Web. doi:10.1063/1.2202566.
Hatfield, D., Casagrande, F., Campisi, I., Gurd, P., Howell, M., Stout, D., Strong, H., Arenius, D., Creel, J., Dixon, K., Ganni, V., & Knudsen, P. SNS Cryogenic Systems Commissioning. United States. doi:10.1063/1.2202566.
Hatfield, D., Casagrande, F., Campisi, I., Gurd, P., Howell, M., Stout, D., Strong, H., Arenius, D., Creel, J., Dixon, K., Ganni, V., and Knudsen, P. Thu . "SNS Cryogenic Systems Commissioning". United States. doi:10.1063/1.2202566.
@article{osti_20800204,
title = {SNS Cryogenic Systems Commissioning},
author = {Hatfield, D. and Casagrande, F. and Campisi, I. and Gurd, P. and Howell, M. and Stout, D. and Strong, H. and Arenius, D. and Creel, J. and Dixon, K. and Ganni, V. and Knudsen, P.},
abstractNote = {The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K cold box (consisting of 4 stages of cold compressors), gaseous helium storage, helium purification and gas impurity monitoring system, liquid nitrogen storage and the cryogenic distribution transfer line system. The overall system commissioning and future plans will be presented.},
doi = {10.1063/1.2202566},
journal = {AIP Conference Proceedings},
number = 1,
volume = 823,
place = {United States},
year = {Thu Apr 27 00:00:00 EDT 2006},
month = {Thu Apr 27 00:00:00 EDT 2006}
}
  • The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K cold box (consisting of 4 stages of cold compressors), gaseous helium storage, helium purification and gas impurity monitoring system, liquid nitrogen storage and the cryogenic distribution transfer line system. The overall system commissioning and future plans will be presented.
  • The largest cryogenic test facility at CERN, located at Zone 18, is used to validate and to test all main components working at cryogenic temperature in the LHC (Large Hadron Collider) before final installation in the machine tunnel. In total about 1300 main dipoles, 400 main quadrupoles, 5 RF-modules, eight 1.8 K refrigeration units will be tested in the coming years.The test facility has been improved and upgraded over the last few years and the first 18 kW refrigerator for the LHC machine has been added to boost the cryogenic capacity for the area via a 25,000 liter liquid heliummore » dewar. The existing 6 kW refrigerator, used for the LHC Test String experiments, will also be employed to commission LHC cryogenic components.We report on the design and layout of the test facility as well as the commissioning and the first 10,000 hours operational experience of the test facility and the 18 kW LHC refrigerator.« less
  • The Spallation Neutron Source (SNS) superconducting linac has been commissioned in 2005 with an output beam energy tuned up to 950 MeV and a peak beam current of approximately 40 mA. Some of the most important contributions to the successful beam commissioning of the world's first pulsed proton SC linac are discussed in this paper, including cryomodule commissioning, numerical modeling for beam acceleration and transport in the accelerator, as well as the development of superconducting linac tune-up algorithms. Beam commissioning results and some beam dynamics studies of the SNS linac are also briefly described.
  • The use of superconducting radiofrequency (SRF) cavities in particle accelerator is becoming more widespread. Among the projects that make use of that technology is the Spallation Neutron Source, where H-ions are accelerated to about 1 GeV, mostly making use of niobium elliptical cavities. SNS will use the accelerated short (about 700 ns) sub-bunches of protons to generate neutrons by spallation, which will in turn allow probing structural and magnetic properties of new and existing materials. The SNS superconducting linac is the largest application of RF superconductivity to come on-line in the last decade. The SRF cavities, operated at 805 MHz,more » were designed, built and integrated into cryomodules at Jefferson Lab and installed and tested at SNS. SNS is also the first proton-like accelerator which uses SRF cavities in a pulse mode. Many of the details of the cavity performance are peculiar to this mode of operation, which is also being applied to lepton accelerators (TESLA test facility and X-FEL at DESY and the international linear collider project). Thanks to the low frequency of the SNS superconducting cavities, operation at 4.2 K has been possible without beam energy degradation, even though the cavities and cryogenic systems were originally designed for 2.1 K operation. The testing of the superconducting cavities, the operating experience with beam and the performance of the superconducting linac will be presented.« less
  • The Spallation Neutron Source accelerator systems will deliver a 1 GeV, 1.44 MW proton beam to a liquid mercury target for neutron scattering research. The accelerator complex consists of an H- injector, capable of producing one-ms-long pulses at 60 Hz repetition rate with 38 mA peak current, a 1 GeV linear accelerator, an accumulator ring and associated transport lines. A 2.5 MeV beam from the Front End is accelerated to 86 MeV in a Drift Tube Linac, then to 185 MeV in a Coupled-Cavity Linac and then to 1 GeV in a Superconducting Linac. The staged beam commissioning of themore » accelerator complex is proceeding as component installation progresses. The Front End, Drift Tube Linac and part of the Coupled-Cavity Linac have been commissioned at ORNL. The primary design goals of peak current, transverse emittance and beam energy have been achieved. Results and status of the beam commissioning program will be presented.« less