Progress Towards Completion of the MICE Demonstration of Muon Ionization Cooling

Abstract

The Muon Ionization Cooling Experiment (MICE) at the Rutherford Appleton Laboratory aims to demonstrate 10% ionization cooling of a muon beam by its interaction with low-Z absorber materials followed by restoration of longitudinal momentum in RF linacs. MICE Step IV, including the rst LH 2 or LiH absorber cell sandwiched between two particle tracking spectrometers, is the collaboration's near-term goal. Two large superconducting spectrometer solenoids and one focus coil solenoid will provide a magnetic eld of 4 T in the tracker and absorber-cell volumes. The status of these components is described, as well as progress towards Steps V and VI, including the eight RF cavities to provide the required 8 MV/m gradient in a strong magnetic eld; this entails an RF drive system to deliver 2 MW, 1 ms pulses of 201 MHz frequency at 1 Hz repetition rate, the distribution network to deliver 1 MW to each cavity with correct RF phasing, diagnostics to determine the gradient and the muon transit phase, and development of the large-diameter magnets required for the linacs.