The super omega muon beamline at J-PARC

Abstract

The Materials and Life Science Facility (MLF) is currently under construction at J-PARC in Tokai, Japan. The facility houses both muon (graphite) and neutron (mercury) production targets, and is located at the end of the 3 GeV proton beamline. The Super Omega muon beamline (one of four secondary muon beamlines) extends at 45° into backward angles to transport the surface μ + and cloud μ − to experimental hall 2. Once completed, it will produce the highest intensity pulsed muon beam in the world, with 4×10 8 μ +/s and 10 7 μ −/s, which will be used for a variety of purposes such as experiments in muon-catalyzed fusion and the production of ultra-slow muons. The beamline consists of normal-conducting capture solenoids, superconducting transport solenoids, and a Dai Omega-type axial focusing magnet. Currently, the construction of the capture solenoids is nearing completion. The design of the transport solenoids is under way, and tests solenoids will be fabricated and tested during the summer of 2008. The axial focusing magnet, used to focus the muon beam on the experimental target, is under consideration with particular emphasis on its compatibility with the transport solenoids.