JEMMRLA - A proof of concept for optimal recirculating linac acceleration for muon colliders and neutrino factories

Neutrino factories and muon colliders require rapid acceleration of muon beams. A Recirculating Linear Accelerator (RLA) is an efficient way of accelerating electrons, muons or light ions to medium and high energies by reusing the same linac for multiple passes. In a conventional RLA, the beams of different energies are separated and sent to individual arcs for recirculation. We have proposed a novel high momentum acceptance return arc designed to transport more than one orbit as a fast and economical mean of achieving this goal. We aim to test this concept by building a small machine, Jefferson Lab Electron Model for Muon Recirculating Linac Acceleration (JEMMRLA). Scaling the muon momentum by the muon to electron mass ratio and changing the RF frequency from 200 MHz to 1.5 GHz leads to a compact machine which fits in a 25x7 m footprint. The electron beam of initial momentum of 4.5 MeV/c is injected at the center of the linac comprised of two 1.5GHz cavities. The recirculating arcs are made of fixed field combined function magnets providing quadrupole and dipole field.