Fermilab, Batavia, USA
The commissioning of two cryomodule components is underway at Fermilab’s Superconducting Radio Frequency (SRF) Accelerator Test Facility. The research at this facility supports the next generation high intensity linear accelerators such as the International Linear Collider (ILC), a new high intensity injector (Project X) and other future machines. These components, Cryomodule #1 (CM1) and Capture Cavity II (CC2) which contain 1.3 GHz cavities are connected in series in the beamline and through cryogenic plumbing. Studies regarding characterization of ground motion, technical and cultural noise continue. Mechanical transfer functions between the foundation and critical beamline components have been measured and overall system displacement characterized. Baseline motion measurements given initial operation of cryogenic, vacuum systems and other utilities are considered.
Fermilab, Batavia, USA
The low-beta section of the linac being considered for Project X at Fermilab contains several styles of 325 MHz superconducting single spoke cavities and solenoid based focusing lenses, all operating at 2 K. Each type of cavity and focusing lens will eventually be incorporated into the design of cryomodules unique to various sections of the linac front end. This paper describes the design of a multiple-cavity and solenoid cryomodule being developed to test the function of each of the main cryomodule systems – cryogenic systems and instrumentation, cavity and lens positioning and alignment, conduction-cooled current leads, magnetic shielding, cold-to-warm beam tube transitions, interfaces to interconnecting equipment and adjacent modules, as well as evaluation of overall assembly procedures.
Fermilab, Batavia, USA
Fermilab is developing 325 MHz SRF spoke cavities for the proposed ProjectX. A compact fast/slow tuner has been developed to compensate microphonics and Lorentz force detuning. The modified tuner design and results of 4K tests of the first prototype are presented.
Fermilab, Batavia, USA
INFN/LASA, Segrate (MI), Italy
Fermilab is building Cryomodule 2 for ILCTA facility at NML. A coaxial blade tuner has been chosen for the CM2 1.3GHz SRF cavities. A summary of results from cold test of the tuners in the Fermilab Horizontal Test Stand will be presented.
Fermilab, Batavia, USA
The proposed multi-MW Project X facility at Fermilab will employ cavities with bandwidths as narrow as 20 Hz. This combination of high RF power with narrow bandwidths combined requires careful attention to detuning control if these cavities are to be operated successfully. Detuning control for Projects X will require a coordinated effort between the groups responsible for various machine subsystems. Considerable progress in this area has been made over the past year.
Fermilab, Batavia, USA
INFN-Pisa, Pisa, Italy
An adaptive Least Squares algorithm to control Lorentz force detuning in SRF cavities has been developed and tested in the HTS at FNAL. During open-loop tests in the FNAL HTS, the algorithm was able to reduce LFD in a 9-cell 1.3 GHz elliptical cavity operating at 35 MV/m from 600 Hz to less than 10 Hz during both the fill and the flattop. The algorithm was also able to adapt to changes in the gradient of the cavity and to changes in the pulse length.
Fermilab, Batavia, USA
Fermilab, Batavia, USA
At Fermilab, 9-cell 1.3 GHz superconducting RF (SRF) cavities are prepared, qualified, and assembled into cryomodules, for Project X, an International Linear Collider, or other future projects. The 1.3 GHz SRF cavity program includes targeted R&D on 1-cell 1.3 GHz cavities for cavity performance improvement. Production cavity qualification includes cavity inspection, surface processing, clean assembly, and one or more cryogenic low-power CW qualification tests which typically include performance diagnostics. Qualified cavities are welded into helium vessels and are cryogenically tested with pulsed high-power. Well performing cavities are assembled into cryomodules for pulsed high-power testing in a cryomodule test facility, and possible installation into a beamline. The overall goals of the 1.3 GHz SRF cavity program, supporting facilities, and accomplishments are described.