A high-power positron converter based on a recirculated liquid metal in-vacuum target

An effective high power positron converter for electron Linacs is not currently available from industry. A commercial source allows the nation's research institutes to have ready access to high brightness positrons for a wealth of material science, nuclear, particle, and accelerator physics projects. Improving the efficiency of the converter target will allow these projects to proceed without in-house development and translates into lower operating costs and the ability to operate with higher beam currents. By focusing on the total particle shower after the converter, not just positrons, we will reduce the irradiation of nearby accelerator components, minimizing the activation and degradation of those components. This means that one does not have to wait for the radioactivity to decay to access the accelerator vault for maintenance, an important consideration for high energy facilities operating around the clock. During this project, an effective positron converter centered around a free surface GaInSn liquid metal jet will be designed. Free surface liquid metal jets allow for significantly greater electron beam power densities than possible with solid targets. Higher power densities lead to greater positron production and importantly, allow CW operation. By considering electron energies in the 10 and 80 MeV range, this project will lead to positron (including polarized positrons are an important consideration for Jefferson Lab in the future) sources that will be of benefit to researchers in the nuclear, solid state, and low energy particle physics communities. The team at Xelera Research LLC is uniquely experienced in the design and construction of novel optics, detectors, particle beam sources, injectors, beam transport systems, and beam dumps, and has pioneered work with using modern optimization techniques for applications of interest to the Department of Energy.