Development of a 400 MHz Superconducting RF Crabbing Cavity

Superconducting radio frequency (SRF) cavities are being successfully used for acceleration of charged particle beams worldwide. The application of the SRF cavities for manipulation of the beam properties in the transverse direction is both immanent and appropriate. The use of superconducting (SC) structures helps maximize the accelerating gradient, which is a highly desirable trait for applications involving manipulations of the charged particle beams at the point of delivery, such as Final Focus point or the experimental areas. Application of the parallel bar SC structure in future SRF accelerators will allow a further increase of the existing machines performance. Compact equipment utilizing SRF cavities can be successfully used in the broad range of applications from increasing of the beam luminosity in colliders, manipulation of the correlation between the longitudinal and transverse phase space projections of the beam particle distribution, to assistance in generation of the sub-picosecond x-ray pulses. This STTR proposal will develop a 400 MHz superconducting parallel-bar crabbing cavity capable of tilting the proton beam with energy of up to 7 TeV at the Final Focus point with help of a single unit. The transverse size of the cavity is significantly reduced using the parallel-bar geometry compared to the traditional elliptical accelerating structures. In collaboration with Niowave, Phase I demonstrated the technical feasibility of the project by completing the preliminary cavity and cryomodule designs. Phase II will finalize the design, and then fabricate and test the SRF parallel-bar crabbing cavity. The cavity is designed to operate at 400 MHz and is capable of generating transverse electric voltage of up to 5 MV in a single unit with electric and magnetic surface peak fields of no more than 50 MV/m and 150 mT respectively. Cryogenic tests will be carried out by Old Dominion University (ODU) in collaboration with the Thomas Jefferson National Laboratory (JLAB). Demonstration of this new type of SRF crabbing cavity creates many new possibilities for scientific and industrial applications.