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Recent measurements by the Birmingham group of the scattering and polarization of 29 MeV 3He particles are analysed in terms of a simplified version of the strong absorption, model. The differential elastic scattering cross section σ(θ) and the polarization P(θ) for 12C Sn and Au are fitted by means of three parameters. The values of the parameters for scattering of 3He by different nuclei are found to be consistent. An estimate of the 3He-nucleus spin-orbit interaction indicates that its magnitude is similar to that of the nucleon-nucleus spin-orbit interaction.

Recently, shell model wave functions for low-lying nuclear states in the range 29Si-40Ca with intermediate coupling and configurational mixing, have been calculated. In this paper these wave functions are used to obtain numerical values for magnetic dipole moments and magnetic dipole transition rates. Expressions are given for the matrix elements of the magnetic dipole operator in terms of single-particle matrix elements. The ground state magnetic moments and the widths for M1 transitions to the ground state are calculated (i) with single-particle g values; (ii) with effective g values) for the nuclei in the range 29Si-40Ca. The results are tabulated.

In the energy range Eα = 2.10−3.25 MeV, twenty-three resonances are reported from radiative alpha capture in 30Si. For the thirteen strongest resonances the main modes of decay and the resonance strengths are given. Angular distribution and angular correlation measurements yield the spin and parity of nine Jπ = 1− resonances and of three Jπ = 2+ resonances. Comparison of the radiative widths of E1 transitions in the compound nucleus 34S, as calculated from the measured resonance strengths, with those of analogous E1 transitions in 32S, indicates that in this mass-region the isobaric-spin selection rule inhibits the E1 transition speed in self-conjugate nuclei by about one order of magnitude.

Shell model calculations on nuclei in the region 28 < A "< 40 are performed with the as- sumption of an inert 2aSi core. The theory underlying these calculations has been described in an earlier paper. The numerical results are presented here. The values of the two-particle interac- .tions in the 2s~ ld t shell and the binding energies to the ~sSi core of 2s~ and ld t particles are derived from experimental level energies. The calculated energies, spins and configurations of about 400 levels are listed. With the nuclear wave functions obtained, the spectroscopic factors for stripping reactions are calculated and, where possible, compared with the experimental data. (two-particle) interactions between nucleons in the various configurations of the 2s~ 1 d~t shell can be expressed in terms of fifteen interaction energies of two-particle configurations. With the binding energies (to the 28Si core) of a nucleon in the 2s~ shell and in the ld~ shell one thus obtains seventeen parameters in terms of which the interaction matrix elements of the nuclear Hamiltonian can be expressed. Most of the necessary two-particle interactions are diagonal; however, some non-diagonal inter- actions are also needed to evaluate the mixing between states of different configura- tions, but with the same spin and isospin. The best values of the seventeen parameters are obtained from a least-squares fitting procedure, in which computed energies are compared with energies of a number of states with experimentally well-known spin and isospin. This requires linearization and iteration processes, also described in paper I. A tentative set of the parameters was obtained by a preliminary inspection of the experimental data and comparison with Arima's results 2). For the first run on the computer only the energies of ground states and a few first excited states were utilized. With the parameters obtained in this way, the energies of more states were computed and compared with experiment. Some of these states were selected and taken along in the next computer run. This process was repeated several times. Altogether fifty states were taken along in the final fitting procedure. With the values of the parameters thus obtained, the energies and wave functions

In the energy range E alpha = 2.10 to 3.25 Mev, twenty-three resonances are reported from radiative alpha capture in /sup 30/Si. For the thirteen strongest resonances, the main mode of decay and the resonance strengths are given. Angular distribution and angular correlation measurements yield the spin and parity of nine 1/sup -/ resonances and of three 2/sup +/ resonances. Comparison of the radiative widths of E1 tran sitions in the compound nucleus / sup 34/S, as calculated from the measured resonance strengths, with those of analogous E1 transitions in /sup 32/S, indicates that in this mass-region the isobaric-spin selection rule inhibits the E1 transition spee in self-conjugate nuclei by about one order of magnitude. (auth)