Jaroslaw Pasternak (Imperial)

Demonstration of muon beam cooling using the Muon Ionization Cooling Experiment (MICE) at RAL

Abstract: A Muon Collider has been proposed as a facility to search for new phenomena in lepton-antilepton collisions at extremely high energy and to study the Higgs properties facilitated by the large, compared to electron, muon mass. Muon beams may also provide uniquely well-characterised neutrino beams, if injected into a ring with long straight sections in the so called Neutrino Factory. Muon beams may be created through the decay of pions produced in the interaction of a proton beam with a target. Such "tertiary" beams have much lower brightness than those created by accelerating electrons, protons or ions. Ionization cooling is a novel technique by which it is proposed to increase muon beam brightness. Muon Ionisation Cooling Experiment (MICE) at RAL has recently reported on the first demonstration of ionization cooling. Ionization cooling was demonstrated by observing an increase in the number of muons having low amplitude on passage through an absorber and an increase in the corresponding phase-space density. The simulated performance of the ionization cooling system was consistent with that measured. The good agreement of the simulation validates ionization-cooling channel designs in which the ionization cooling process is repeated to produce a substantial cooling effect. The measurements presented here therefore demonstrate that an ionization cooling channel can produce the beam quality required for a Muon Collider and can be used to increase performance of the Neutrino Factory. Imperial is one of the leading institutes in MICE and the key Imperial contributions are highlighted.