The J-PARC E34 experiment aims to measure muon's anomalous magnetic moment and electric dipole moment with ultra-high precision by utilizing an ultra-cold muon beam. The ultra-cold muon beam spreads very little in transverse directions even after a long distance of travel, thanks to a muon source that is cooled down to thermal energies. The beam is prepared by accelerating the thermal-velocity muons generated by laser-resonant ionization of atoms of muonium (a bound state of a positive muon and an electron). The ultra-cold muon beam is stored in a super-high precision magnet where spin precession of muons in a magnetic field is measured by detecting muon decay.
We plan to realize the measurement with the intense pulsed proton beam at J-PARC and state of the art technologies, such as an intense Lyman-alpha laser, the first-ever muon acceleration LINAC, precision magnetic field control, and particle tracking.