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A β-NMR study of 12B implanted in diamond was performed in order to investigate the implantation sites and the defects. The maintained polarization of 12B was measured by use of widely modulated rf around the Larmor frequency (ν = νL ± 200 kHz) as a function of temperature from 160 K to 320 K. The observed polarization was found to be almost constant at about 0.9 % in this temperature range. The initial polarization for this system was obtained as about 8.1 %. Therefore about 10 % of the implanted 12B maintained its polarization in this frequency range. Conversely, about 90 % of the implanted 12B was undetected in the present experiment.

Spin polarization of short-lived β-emitting nucleus 29P (Iπ = 1/2 + , T1/2 = 4.14 s) produced through the 28P(d, n) 29P reaction was studied as functions of the incident deuteron energy Ed and the recoil angle θ of 29P. New optimum condition was found at Ed = 3.3 MeV and θ = 30° where polarization of 29P is −(4.1 ± 0.7) %.

Polarized UCNs have been created by selecting only one spin state passing through a magnetized Fe foil. Typical degree of polarization was about 90 %. The polarization relaxation time in the prototype Ramsey cell was \(T_1 =1100^{+800}_{-400}\) s. Clear Ramsey resonance spectra have been observed for two precession time settings, tc = 100 ms and 30 s. The transverse relaxation time T2 was about 50 s.

We report our studies in various fields of Physics through nuclear moments utilizing the β-NMR technique, including material sciences, nuclear structures and fundamental symmetries. Especially, we focus on the recent progress in the studies on the electronic structure in Pt through Knight shifts of various impurities, lattice locations of impurities, electric field gradients, the analysis of nuclear spin in terms of its components, anomaly in the spin expectation value for 9C-9Li mirror pair, the G-parity conservation law, and the Ramsey resonance on UCN for future neutron EDM measurements.

The degrees of polarization of proton rich nucleus 28P produced in charge exchange reactions 28Si + 9Be → 28P + X, and 28Si + 1H → 28P + X have been observed at 100A MeV. Utilizing thus obtained polarized nuclei, the magnetic moment of 28P was remeasured, and |μ(28P)| = 0.3115 (34) μN was obtained. β-nuclear quadrupole resonance (β-NQR) of 28P implanted in α-Al2O3 have been observed for the first time, in order to measure the electric quadrupole moment of this nucleus.

Electric quadrupole coupling constant eqQ/h of the extremely proton-rich 23Al (I π = 5/2 + , T 1/2 = 0.47 s) nucleus implanted into an Al2O3 single crystal has been measured for the first time, using the β-ray detecting nuclear quadrupole resonance method (β-NQR) in a high magnetic field. As a preliminary result, the quadrupole coupling constant was determined as |eqQ/h(23Al) | = 2.66±0.77 MHz. Using the quadrupole coupling constant of 27Al in Al2O3 as a reference, the Q moment of the ground state of 23Al was extracted as |Q(23Al)| ~ 160 mb, which is well explained by the shell model calculation in the sd-shell model space with the USD interaction.

The magnetic moment of short lived β-emitter 24mAl (426 keV, Iπ = 1 + , T1/2 = 131 ms) has been measured by means of β-NMR technique, for the first time. From the β-NMR spectrum, the magnetic moment was determined as \(\left| {\upmu}\left( ^{\rm 24m}{\rm Al} \right) \right|=\left( {2.99\pm 0.09} \right){\upmu}_{\rm N}\). Combined with the known magnetic moment of the mirror partner 24mNa, the expectation value of is obtained to be (0.08 ± 0.12). These values are reproduced well by the shell model calculation.

The spin-lattice relaxation times T1 for short-lived β emitters 25Al(I = 5/2, T1/2 = 7.2 s) and 28P(I = 3, T1/2 = 270 ms) in Pt were measured by means of the β-NMR technique. As a result, T1[25Al in Pt] = (1.1 \(^{+\ 0.7}_{-\ 0.3})\) s and T1[28P in Pt] >0.5 s were obtained at temperatures of 17 and 20 K, respectively. The Knight shifts were estimated from the Korringa relation, which were evaluated by comparing to the first principle calculations.

Hyperfine interactions of Na isotopes in single crystals have been studied using highly nuclear polarized 20,21,26,27,28Na beams provided by ISAC/TRIUMF. The degree of polarization kept in the crystals, the spin-lattice relaxation times, the electric quadrupole coupling constants and the initial distribution of the populations were measured. Such knowledge is indispensable for the application of the hyperfine interactions in the study of precision measurements such as the nuclear structure through nuclear moments and the fundamental symmetries.

The electric quadrupole coupling constants eqQ/h of 20Na (Iπ = 2+, T 1/2 = 449.7 ms), 21Na (Iπ = 3/2, T 1/2 = 22.49 s) and 25Na (Iπ = 5/2, T 1/2 = 59.6 s) in single crystal ZnO and TiO2 were precisely measured by applying the β-NMR technique. The ratio of the quadrupole moments between 20Na (25Na) and 21Na was determined to be 0.728 ± 0.023 (0.011 ± 0.002).

The Knight shifts K and the spin-lattice relaxation time T 1 for the short-lived s-emitters 12B and 12N implanted into Pd have been measured by means of the s-NMR method. The results show that K depends on temperature. The obtained values of experimental K were compared with theoretical values derived with the KKR method.

More than half of the Japanese patients with 2,8-dihydroxyadenine urolithiasis only partially lack adenine phosphoribosyltransferase (APRT), while all the Caucasian patients with the same disease completely lack the enzyme. APRT activities in healthy heterozygotes for the complete APRT deficiencies were at the same levels as the Japanese patients, and simple enzyme assay does not distinguish between these two conditions. We have previously shown, using viable T-cells, that the enzyme was non-functional in the cells from the Japanese patients although they contain considerable APRT activities in the cell extracts. In the present investigations, we devised a rapid method using erythrocytes for the diagnosis of partial APRT deficiencies accompanied by severe impairment in adenine metabolism causing 2,8-dihydroxyadenine lithiasis. Thus, erythrocytes from three different families with 2,8-dihydroxyadenine urolithiasis associated with partial APRT deficiencies incorporated only minimal amounts of radioactive adenine, while normal erythrocytes incorporated significant amounts. These data indicate that severe impairment in adenine metabolism is shown not only in viable T-cells but also in viable erythrocytes. The present procedures provide a rapid method suitable for routine clinical use for the diagnosis of partial APRT deficiencies causing 2,8-dihydroxyadenine lithiasis.