[en] The two-deuteron-alpha-particle overlap, including its D-wave component, is evaluated in the case of realistic two- and four-body wavefunctions. The deduced theoretical value is compared with improved empirical estimates based upon DWBA analyses of (d,α) reactions in the sd shell and which incorporate the best available shell-model information for the nuclear states involved. The theoretical and empirical values of this analysis are in agreement. The result differs substantially from other recent empirical estimates obtained from (d,α) reactions upon heavier target nuclei and from simple theoretical estimates which make use of a point-deuteron approximation. (author)

[en] The effects of Coulomb stretching of the deuteron internal wavefunction upon calculated tensor analyzing powers, in the reaction ²⁰⁸Pb(d(pol),p)²⁰⁹Pb, are studied quantitatively, and shown to be small but not negligible. (Auth.)

[en] The spin-dependence of the interaction between a deuteron and a heavy target nucleus at low bombarding energies, resulting from coupling between the deuteron elastic, and (d,p) transfer reaction channels, is studied quantitatively. By use of approximate two-step distorted wave Born approximation calculations, deuteron D-state effects are easily included. In the case of a ²⁰⁸Pb target, transfer channel coupling and not the folding model spin-dependent interactions, are shown to be primarily responsible for the experimentally observed spin-dependence of the deuteron elastic scattering at sub-Coulomb barrier energies. (orig.)

[en] The two-deuteron-alpha-particle overlap, including its D-wave component, is calculated for realistic two- and four-body wave functions. The deduced theoretical D/sub 2/ (d,α) value is compared with improved empirical estimates from DWBA analyses of (d,α) reactions in the sd-shell and with other recent theoretical and empirical estimates

[en] The recent suggestion that the effects of a D-state component of the α particle are being seen in (d, α) reaction tensor analyzing power data is reexamined using exact finite range distorted-wave Born approximation calculations. Results for ³²S(d,α)³⁰P(g.s.), at E = 16 MeV, are at considerable variance with two-nucleon-core relative motion amplitudes derived from shell model calculations

[en] Corrections to the Alder and Winther semiclassical cross section for first order Coulomb excitation are considered through the Sukumar and Brink systematic expansion of the propagator in inverse powers of Sommerfeld's parameter, η. The zeroth order term is that provided by unsymmetrised Alder-Winther theory and it is shown that to order 1/η the only type of correction is one corresponding to energy symmetrisation. (orig.)

[en] It is shown that, for sub-Coulomb incident deuteron energies, coupling to weakly bound neutron transfer channels produces large changes in the calculated elastic channel vector analysing powers, iT¹¹ as compared with those obtained using a folding model spin-orbit interaction. Coupled channels calculations for deuteron scattering from ₂₀₈Pb at 8 MeV and 9 MeV are in quantitative agreement with the experimental iT¹¹ data. (orig.)

[en] Motivated by much recent discussion of the N=8 neutron shell closure, we review the theoretical description of ¹²Be within a three-body (n+n+¹⁰Be) model with core excitation. Agreement with recently deduced <¹¹Be|¹²Be> spectroscopic factors requires a smaller deformation of the ¹⁰Be core in ¹²Be than in ¹¹Be, with a reduced role for core excitation. Observables for the ground state and 2⁺, 1^- and 0⁺₂ excited states of ¹²Be are presented. Limitations and improvements of the model are discussed

[en] The heavy beryllium isotopes ¹³Be and ¹⁴Be are described as one- and two-neutrons outside of a deformed ¹²Be core, which is treated as a rigid rotor and the neutron-core interaction is approximated by a deformed Woods-Saxon potential. Our three-body description of ¹⁴Be uses the hyperspherical expansion formalism, including the core degrees of freedom. We explore those potential parameters compatible with the known properties of ¹²Be, ¹³Be and ¹⁴Be. We find that both ¹⁴Be and ¹³Be can be described simultaneously provided the ¹²Be core has a large positive quadrupole deformation

[en] At low energies (≅ 20 MeV) the Johnson-Soper adiabatic model for deuteron break up is inaccurate when applied to transfer reaction calculations. The assumed degeneracy of the n-p centre-of-mass energy in all break-up configurations results in a lack of phase averaging and, in particular, an overestimation of the break-up component of the entrance channel wavefunction near the nuclear surface, of most importance to transfer reactions. This inadequacy of the break-up wavefunction is studied quantitatively and shown not to be significant for application of the adiabatic theory to the (d,p) reaction at 79 MeV incident deuteron energy. (author)