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A new experimental method to search for T-violating transverse muon polarization ( P T ) in the K + → π 0 μ + ν decay has been proposed. In this new experiment, the measurements of the μ + momentum vector, the π 0 momentum vector, and the μ + polarization will be performed by the same electro-magnetic calorimeter. One of main issues is the choice of a scintillation material which can preserve the μ + spin polarization for several μ + lifetimes. A test experiment to measure the μ + polarization in various scintillating crystals was performed at J-PARC Material and Life Science Facility (MLF). We concluded that the μ + polarization in CeF 3 is high enough to perform the new T-violation experiment. [ABSTRACT FROM AUTHOR]

Spin pumping is an interfacial spin current generation from the ferromagnetic layer to the non-magnetic metal at its interface. The polarization of the pumped spin current J s ∝ m × m ˙ depends on the dynamics of the magnetic moment m . When the materials are based on light transition metals, mechanism behind the spin current transfer is dominated by the exchange interaction between spin of localized d-electrons and itinerant conduction electrons. In heavier transition metals, however, the interaction is not limited to the exchange interaction. The spin of the conduction electron can interact to its nuclear spin by means of hyperfine interaction, as observed in the shift of NMR frequency. By studying the spin polarization of conduction electron of the non-magnetic metallic layer due to a nuclear magnetic moment I of the ferromagnetic layer, we show that the hyperfine interaction can mediate the spin pumping. The polarization of the spin current generation is shown to have a similar form J s ∝ I × I ˙ . [ABSTRACT FROM AUTHOR]

The beta-detected nuclear magnetic resonance ( β-NMR) in liquid HO has been observed for the first time using a short-lived β-ray emitter N ( I = 1, T =11 ms). A nuclear spin polarized N beam with an energy of about 20 MeV/nucleon was implanted into an enclosed water sample. About 50 % of implanted N ions maintained nuclear polarization and exhibited a β-NMR spectrum. The chemical shift of N in HO relative to N in Pt was deduced to be −(3.6±0.5) × 10 ppm. [ABSTRACT FROM AUTHOR]

We demonstrate spin-exchange optical pumping of Xe atoms with our newly made laser system. The new laser system was prepared to provide higher laser power required for the stable operation of spin maser oscillations in the Xe EDM experiment. We studied the optimum cell temperature and pumping laser power to improve the degree of Xe spin polarization. The best performance was achieved at the cell temperature of 100 C with the presently available laser power of 1 W. The results show that a more intense laser is required for further improvement of the spin polarization at higher cell temperatures in our experiment. [ABSTRACT FROM AUTHOR]

Spin polarized positive muons injected in matter serve as magnetic probes for the investigation of physical and chemical properties of free radicals, mechanisms of free radical reactions and their formations, and radiation effects. All muon techniques rely on the evolution of spin polarization (of the muon) and in that respect are similar to conventional magnetic resonance techniques. The applications of the muon as a hyperfine probe in several fields in chemistry are described. [ABSTRACT FROM AUTHOR]

The ASACUSA collaboration has developed a cusp trap scheme to realize an in-flight high precision microwave spectroscopy of ground-state hyperfine splitting of antihydrogen ( H̄) for a stringent test of CPT symmetry. Cold H̄ atoms were successfullysynthesized by employing a cusp trap which consisted of a superconducting anti-Helmholtz coil and a stack of ring electrodes. This was achieved with an antiproton ( p̄) accumulator, MUSASHI, and a positron ( e+) accumulator. The principal quantum number and the time evolution of H̄ synthesis were investigated. The latest progress was also presented. [ABSTRACT FROM AUTHOR]