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Spin-polarized radioactive ion beams are produced in the projectile fragmentation reaction induced by intermediate-energy heavy ion beams. The degree of spin polarization shows characteristic dependence on the outgoing momentum of the projectile fragment in the magnitude around 1∼10%. The qualitative behavior is well described by the kinematical model of the fragmentation process. Recently, we have successfully produced spin-polarized beams of aluminum isotopes in the mass A∼30 region via the fragmentation of 95 MeV/u 40Ar projectiles. The magnetic moments of 30Al and 32Al and the electric quadrupole moments of 31Al and 32Al have been measured using the β-NMR technique with the polarized RI beams of the Al isotopes. [ABSTRACT FROM AUTHOR]

Based on the technique of fragment-induced spin polarization combined with the β-NMR method, a series of experiments has been carried out at RIKEN for the nuclear-moment measurement of light unstable nuclei. The measurement will be extended further in the RIKEN RIBF project, where radioactive-isotope beams in the medium- and heavy-mass regions will be produced at higher energies and with higher intensities compared with the RARF facility. Measurements of the isomeric-state nuclear moments of unstable nuclei will be started with BigRIPS by utilizing fragment-induced spin-orientation phenomena. Also, an upgrade program of the existing fragment separator RIPS is proposed in the phase-II program of RIBF. Then, intense beams will be delivered to RIPS at E ∼ 115 A MeV. This energy region is useful, not only because spin orientation is produced in the PF reaction but also they can be implanted into sample materials with limited thickness. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The electric quadrupole moment Q for the ground state of 32Al has been measured using the β-NMR technique. Spin-polarized 32Al nuclei were obtained from the fragmentation of 40Ar projectiles at E/A = 95 MeV/nucleon, and were implanted in a single crystal α-Al2O3 stopper. The quadrupole moment was deduced from the measured quadrupole coupling constant. The obtained value, |Q(32Alg.s.)| = 24(2) mb, was well reproduced by shell model calculations within the sd shell, indicating that 32Al is a normal sd-shell nucleus. The result is in sharp contrast to the strongly deformed nuclei 32Mg and 31Mg neighboring the 32Al isotope. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The electromagnetic moment is a sensitive probe to investigate microscopic structure. In order to measure the electromagnetic moment, β-NMR and β-NQR methods are employed taking advantage of the fragment spin polarization produced by the fragmentation reaction. The measurement of the electric quadrupole moment for ground-state 31Al has been been carried out by β-NQR method. Spin-polarized 31Al nuclei were obtained from the fragmentation of 40Ar projectiles, and were implanted in α-Al2O3 stopper. The electric quadrupole moment was deduced from the measured quadrupole coupling constant. The obtained value is |Q(31Al)| = 104(9) e·mb. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The development of techniques to produce low-energy spin-polarized radioactive nucleon beams (RNBs) is reported. It employs the inverse-kinematics reactions of law energy heavy-ion beams for the RNB production with in-flight separator. Some plans of research are discussed that apply these well-focused, conveniently energetic spin-polarized RNB to nuclear structure physics and material science. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]