FRIB, East Lansing, USA
JLab, Newport News, Virginia, USA
INFN/LNL, Legnaro (PD), Italy
KEK, Ibaraki, Japan
BNL, Upton, Long Island, New York, USA
ANL, Argonne, Illinois, USA
TRIUMF, Vancouver, Canada
Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Cooperative Agreement PHY-1102511.
FRIB, East Lansing, USA
INFN/LNL, Legnaro (PD), Italy
KEK, Ibaraki, Japan
ANL, Argonne, Illinois, USA
TRIUMF, Vancouver, Canada
JLab, Newport News, Virginia, USA
The Facility for Rare Isotope Beams (FRIB), under con-struction at Michigan State University, will utilize a driver linac to accelerate stable ion beams from protons to ura-nium up to energies of >200 MeV per nucleon with a beam power of up to 400 kW. Superconducting technology is widely used in the FRIB project, including the ion sources, linac, and experiment facilities. The FRIB linac consists of 48 cryomodules containing a total of 332 superconducting radio-frequency (SRF) resonators and 69 superconducting solenoids. We report on the design and the construction of FRIB cryomodules.
FRIB, East Lansing, Michigan, USA
NSCL, East Lansing, Michigan, USA
In this paper, a unique low level radio frequency (LLRF) controller designed for a multi-harmonic buncher (MHB) is presented. Different than conventional designs, the single LLRF output contains three RF frequencies (f1, f2 = 2*f1, f3 = 3*f1) and is fed to a wide band amplifier driving the MHB. The challenge is while driving f1, due to the non-linearity of the amplifier, the f2 and f3 terms will also be generated and will couple into the control of these two modes. Hence an active cancellation algorithm is used to suppress the nonlinear effect of the amplifier. It is demonstrated in a test that the designed LLRF is able to control the amplitude and phase of the three modes in-dependently.
FRIB, East Lansing, USA
INFN/LNL, Legnaro (PD), Italy
ANL, Argonne, Illinois, USA
The driver linac for the Facility for Rare Isotope Beams (FRIB) will require the production of 48 cryomodules (CMs). In addition to the β=0.085 quarter-wave CM, FRIB has completed the design of a β=0.53 half-wave CM as a pre-production prototype. This CM will qualify the performance of the resonators, fundamental power couplers, tuners, and cryogenic systems of the β=0.53 half-wave design. In addition to the successful systems qualification; the β=0.53 CM build will also verify the FRIB bottom up assembly and alignment method on a half-wave CM type. The lessons learned from the β=0.085 pre-production CM build including valuable fabrication, sourcing, and assembly experience have been applied to the design of β=0.53 half-wave CM. This paper will report the design of the β=0.53 half-wave CM as well as the CM interfaces within the linac tunnel.
FRIB, East Lansing, Michigan, USA
Northern Illinois University, DeKalb, Illinois, USA
The reaccelerator facility (ReA) at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU) offers a unique capability to study reactions with low-energy beams of rare isotopes. A beam from the coupled cyclotron facility is stopped in a gas stopping system, charge bred in an Electron Beam Ion Trap (EBIT), and then reaccelerated in a compact superconducting LINAC. The original beam repetition rate at the ReA targets was the same as the LINAC RF frequency of 80.5 MHz. In order to add the capability to bunch at a lower frequency (desirable for many types of experiments using time of flight data acquisitions) a 16.1 MHz buncher has been designed, constructed, and commissioned. This paper reports the results of the commissioning of the device, and outlines some future avenues for further improvement of the properties of the bunched beam.