Novel RING Resonator for Laser Ion Stripping

Charge stripping of hydrogen ions is the first stage of any high intensity proton accelerator. Typically, carbon foils are used as strippers; however, the stripping foils introduce uncontrolled beam loss, which is one of the main factors limiting beam power in high intensity proton rings, and have a short life time due to activation. To achieve higher-charge proton sources, the stripping efficiency must be improved, especially in the context of the Spallation Neutron Source at Oak Ridge National Laboratory. A method based on laser-ion interaction has a great potential for increasing efficiency. However, there are some important questions about feasibility of this method due to the high laser power level and the choice of the technology that can deliver the stripping efficiency of near 100%. The approach of this proposed project is to design a laser cavity based on the Recirculation Injection by Nonlinear Gating (RING) technique. In the Phase I project, the RING cavity will be designed and simulated including building the prototype. The goal will be to prepare for Phase II, in which we will build the entire RING system, install, and test it at Spallation Neutron Source at Oak Ridge National Laboratory. Commercial Applications and Other Benefits: If the project is successful, the RING based ion strippers could be employed at a number of proton machines including the Tevatron at Fermilab and Large Hadron Collider at CERN. In addition, there is a number of promising commercial applications, such as in other high intensity proton accelerators for medical proton/ion therapy. The RING technique is also attractive for use in a number of applications that require low loss for the laser pulse, such as production of high photon energies (100 GeV-TeV) via Inverse Compton Scattering mechanism at the International Linear Collider