S. S. Hanna

Electromagnetic moments of short lived beta emitters F-21, Mg-23, Si-27 and Ca-39

The β-NMR spectra of 21F, 23Mg, 27Si and 39Ca which were produced in heavy ion collisions and implanted in various crystals have been observed. The magnetic moments of 21F and 27Si were determined to be |μ(21F)| = 3.9194 ± 0.0012 μN and |μ(27Si)| = 0.8653 ± 0.0003 μN, respectively. The electric quadrupole coupling constants were determined for the first time to be |eqQ(21F in MgF2)/h|= 9.94 ± 0.09 MHz, |eqQ(23Mg in MgF2)/h|= 1.96 ± 0.06 MHz, |eqQ(27Si in Al2O3)/h|= 1.90 ± 0.12 MHz, |eqQ(39Ca in CaCO3)/h|= 0.60 ± 0.04 MHz. From the present eqQ/h, the Q moments were deduced as |Q(21F)|= 110 ± 22 mb, |Q(23Mg)|= 114 ± 3 mb, |Q(27Si)|= 60 ± 13 mb and |Q(39Ca)|= 36± 7 mb. The present data were compared with the theoretical values obtained by the OXBASH shell model code.

Spin polarization of beta-emitting fragments in high energy heavy ions on Be collisions

The degrees of nuclear spin polarization of 8,12B, 9C, 12N, 13O, 20,21F, 23Mg, 27Si and 39Ca produced in the high energy 12,13C, 16O, 22Ne, 24Mg, 28Si and 40Ca ions on Be collisions have been measured systematically, for the technical developments of the nuclear moment studies as well as the hyperfine interaction studies by means of β-NMR technique. The fragment momentum dependences were well reproduced by the simple kinematical model. Incident energy dependence and the mass dependence as well as the reaction angle dependences were qualitatively explained by the mixing of the near and far side collisions.

E1 and E2 Strength in 32s Observed with Polarized Proton Capture

The polarized proton capture reaction is a very powerful tool for studying the giant El resonance as well as M1 and E2 strength in nuclei. The reaction matrix elements for radiative capture can be studied thoroughly if not only the angular distributions, σ(θ), but also the analyzing powers, A(θ), of the emitted photons are observed.

Measurement of the Quadrupole Moment of 8 Li by use of a Polarized Beam and NMR Detection

In a separate contribution to this conference (T. Minamisono et al.) the method of producing polarized nuclei with polarized beams is described. In this paper we report an application of the method to a measurement of the quadrupole moment of 8Li.

Hyperfine Studies by use of Polarized Reactions

A new method for studying hyperfine interactions has been developed in which polarized nuclei are produced from nuclear reactions initiated with fast polarized beams of protons and deuterons. We have demonstrated that in these reactions the net polarization transferred to all residual nuclei is large enough to make possible quantitative studies of nuclear polarization and moments.