THE MICE DEMONSTRATION OF IONIZATION COOLING

Muonbeams of low emittance provide the basis for the intense, well-characterised neutrino beams necessary to elucidate the physics of flavour at the Neutrino Factoryand to provide lepton-antilepton collisions at energies of up to several TeV at the Muon Collider. The International Muon Ionization Cooling Experiment(MICE) will demonstrate ionization cooling, the technique by which it is proposed to reduce the phase-space volume occupied by the muonbeam at such facilities. In an ionization- coolingchannel, the muonbeam passes through a material (the absorber) in which it loses energy. The energy lost is then replaced using RF cavities. The combined effect of energy loss and re-acceleration is to reduce the transverse emittance of the beam (transverse cooling). A major revision of the scope of the project was carried out over the summer of 2014. The revised project plan, which has received the formal endorsement of the international MICE Project Board and the international MICE Funding Agency Committee, will deliver a demonstration of ionization coolingby September 2017. In the revised configuration a central lithium-hydrideabsorber provides the cooling effect. The magnetic lattice is provided by the two superconducting focus coils and acceleration is provided by two 201 MHz single-cavity modules. The phase space of the muonsentering and leaving the cooling cell will be measured by two solenoidal spectrometers. All the superconducting magnets for the ionization coolingdemonstration are available at the Rutherford Appleton Laboratory and the first single-cavity prototype is under test in the MuCool Test Area at Fermilab. The design of the cooling demonstration experiment will be described together with a summary of the performance of each of its components. The cooling performance of the revised configuration will also be presented.