IPAC2011 - Table of Session: MOOCA (Linear Colliders)

Paper

Title

Page

Production and Testing Experience with the SRF Cavities for the CEBAF 12 GeV Upgrade

26

A. Burrill, G.K. Davis, F. Marhauser, C.E. Reece, A.V. Reilly, M. Stirbet
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
The CEBAF recirculating CW electron linear accelerator at Jefferson Lab is presently undergoing a major upgrade to 12 GeV. This project includes the fabrication, preparation, and testing of 80 new 7-cell SRF cavities, followed by their incorporation into ten new cryomodules for subsequent testing and installation. In order to maximize the cavity Q over the full operable dynamic range in CEBAF (as high as 25 MV/m), the decision was taken to apply a streamlined preparation process that includes a final light temperature-controlled electropolish of the rf surface over the vendor-provided bulk BCP etch. Cavity processing work began at JLab in September 2010 and will continue through December 2011. The excellent performance results are exceeding project requirements and indicate a fabrication and preparation process that is stable and well controlled. The cavity production and performance experience to date will be summarized and lessons learned reported to the community.

Slides MOOCA01 [4.376 MB]

MOOCA02

Two Beam Test Stand Experiments in the CTF3 Facility

29

W. Farabolini, F. Peauger
CEA/DSM/IRFU, France
J. Barranco, S. Bettoni, B. Constance, R. Corsini, M. Csatari, S. Döbert, A. Dubrovskiy, C. Heßler, T. Persson, G. Riddone, P.K. Skowroński, F. Tecker
CERN, Geneva, Switzerland
D. Gudkov, A. Solodko
JINR, Dubna, Moscow Region, Russia
M. Jacewicz, T. Muranaka, A. Palaia, R.J.M.Y. Ruber, V.G. Ziemann
Uppsala University, Uppsala, Sweden

The CLEX building in the CTF3 facility is the place where essential experiments are performed to validate the Two-Beam Acceleration scheme upon which the CLIC project relies. The Drive Beam enters the CLEX after being recombined in the Delay loop and the Combiner Ring in intense beam trains of 24 A – 150 MeV lasting 140 ns and bunched at 12 GHz, although other beam parameters are also accessible. This beam is then decelerated in dedicated structures installed in the Test Beam Line (TBL) and in the Two-Beam Test Stand (TBTS) aimed at delivering bursts of 12 GHz RF power. In the TBTS this power is used to generate a high accelerating gradient of 100 MV/m in specially designed accelerating structures. To assess the performances of these structures a probe beam is used, produced by a small Linac. We reported here the various experiences conducted in the TBTS making use of the versatility the probe beam and of dedicated diagnostics.

Slides MOOCA02 [3.003 MB]

MOOCA03

Updates to the International Linear Collider Damping Rings Baseline Design

32

S. Guiducci, M.E. Biagini
INFN/LNF, Frascati (Roma), Italy
G. Dugan, M.A. Palmer, D. L. Rubin
CLASSE, Ithaca, New York, USA
J. Gao, D. Wang
IHEP Beijing, Beijing, People's Republic of China
M.T.F. Pivi, Y. Sun
SLAC, Menlo Park, California, USA
J. Urakawa
KEK, Ibaraki, Japan

A new baseline design for the International Linear Collider (ILC) damping rings has been adopted which reduces the ring circumference to 3.2 km from 6.4 km. This design change is associated with a revised plan to operate the ILC with one half the beam current originally specified in the ILC Reference Design Report. We describe the new layout and lattice that has been developed for the shorter ring. In addition, we discuss features of the new design that will allow operation at a 10Hz repetition rate which is twice the rate specified for baseline operation. Finally, we examine the implications for restoring operation with the originally specified beam current while maintaining the smaller ring circumference.

Slides MOOCA03 [2.381 MB]

Paper	Title	Page
MOOCA01	Production and Testing Experience with the SRF Cavities for the CEBAF 12 GeV Upgrade	26
	A. Burrill, G.K. Davis, F. Marhauser, C.E. Reece, A.V. Reilly, M. Stirbet JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The CEBAF recirculating CW electron linear accelerator at Jefferson Lab is presently undergoing a major upgrade to 12 GeV. This project includes the fabrication, preparation, and testing of 80 new 7-cell SRF cavities, followed by their incorporation into ten new cryomodules for subsequent testing and installation. In order to maximize the cavity Q over the full operable dynamic range in CEBAF (as high as 25 MV/m), the decision was taken to apply a streamlined preparation process that includes a final light temperature-controlled electropolish of the rf surface over the vendor-provided bulk BCP etch. Cavity processing work began at JLab in September 2010 and will continue through December 2011. The excellent performance results are exceeding project requirements and indicate a fabrication and preparation process that is stable and well controlled. The cavity production and performance experience to date will be summarized and lessons learned reported to the community.
	Slides MOOCA01 [4.376 MB]

MOOCA02	Two Beam Test Stand Experiments in the CTF3 Facility	29
	W. Farabolini, F. Peauger CEA/DSM/IRFU, France J. Barranco, S. Bettoni, B. Constance, R. Corsini, M. Csatari, S. Döbert, A. Dubrovskiy, C. Heßler, T. Persson, G. Riddone, P.K. Skowroński, F. Tecker CERN, Geneva, Switzerland D. Gudkov, A. Solodko JINR, Dubna, Moscow Region, Russia M. Jacewicz, T. Muranaka, A. Palaia, R.J.M.Y. Ruber, V.G. Ziemann Uppsala University, Uppsala, Sweden
	The CLEX building in the CTF3 facility is the place where essential experiments are performed to validate the Two-Beam Acceleration scheme upon which the CLIC project relies. The Drive Beam enters the CLEX after being recombined in the Delay loop and the Combiner Ring in intense beam trains of 24 A – 150 MeV lasting 140 ns and bunched at 12 GHz, although other beam parameters are also accessible. This beam is then decelerated in dedicated structures installed in the Test Beam Line (TBL) and in the Two-Beam Test Stand (TBTS) aimed at delivering bursts of 12 GHz RF power. In the TBTS this power is used to generate a high accelerating gradient of 100 MV/m in specially designed accelerating structures. To assess the performances of these structures a probe beam is used, produced by a small Linac. We reported here the various experiences conducted in the TBTS making use of the versatility the probe beam and of dedicated diagnostics.
	Slides MOOCA02 [3.003 MB]

MOOCA03	Updates to the International Linear Collider Damping Rings Baseline Design	32
	S. Guiducci, M.E. Biagini INFN/LNF, Frascati (Roma), Italy G. Dugan, M.A. Palmer, D. L. Rubin CLASSE, Ithaca, New York, USA J. Gao, D. Wang IHEP Beijing, Beijing, People's Republic of China M.T.F. Pivi, Y. Sun SLAC, Menlo Park, California, USA J. Urakawa KEK, Ibaraki, Japan
	A new baseline design for the International Linear Collider (ILC) damping rings has been adopted which reduces the ring circumference to 3.2 km from 6.4 km. This design change is associated with a revised plan to operate the ILC with one half the beam current originally specified in the ILC Reference Design Report. We describe the new layout and lattice that has been developed for the shorter ring. In addition, we discuss features of the new design that will allow operation at a 10Hz repetition rate which is twice the rate specified for baseline operation. Finally, we examine the implications for restoring operation with the originally specified beam current while maintaining the smaller ring circumference.
	Slides MOOCA03 [2.381 MB]