Fusion excitation functions for
16,17O +
144Sm
have been measured to high precision. The extracted fusion barrier distributions show a double-peaked structure interpreted in terms of coupling to ...inelastic collective excitations of the target. The effect of the positive Q-value neutron stripping channel is evident in the reaction with
17O. Fission and evaporation residue cross-sections and excitation functions have been measured for the reaction of
16O +
208Pb
and the fusion barrier distribution and fission anisotropies determined. It is found that the moments of the fusion ℓ-distribution determined from the fusion and fission measurements are in good agreement.
The ground state of the proton-rich nucleus 23Al has been studied by one-proton removal on a carbon target at about 50 MeV/nucleon using the EXOGAM + SPEG experimental setup at GANIL. Longitudinal ...momentum distributions of the 22Mg breakup fragments, inclusive and in coincidence with gamma rays de-exciting the residues, were measured. The ground-state structure of 23Al is found to be a configuration mixing of a d-orbital valence proton coupled to four core states - 0\(^{+}_{gs}\), 2\(^{+}_{1}\), 4\(^{+}_{1}\), 4\(^{+}_{2}\). We confirm the ground state spin and parity of 23Al as \(J^{\pi} = 5/2^{+}\). The measured exclusive momentum distributions are compared with extended Glauber model calculations to extract spectroscopic factors and asymptotic normalization coefficients (ANCs). The spectroscopic factors are presented in comparison with those obtained from large-scale shell model calculations. We determined the asymptotic normalization coefficient of the nuclear system \(^{23}\)Al\(_{gs}\) \(\rightarrow\) \(^{22}\)Mg(0\(^{+}\)) + p to be \(C^{2}_{d_{5/2}}\)(\(^{23}Al_{gs}\)) = (3.90 \(\pm\) 0.44) \(\times\) 10\(^{3}\) fm\(^{-1}\), and used it to infer the stellar reaction rate of the direct radiative proton capture \(^{22}\)Mg(p,\(\gamma\))\(^{23}\)Al. Astrophysical implications related to \(^{22}\)Na nucleosynthesis in ONe novae and the use of one-nucleon breakup at intermediate energies as an indirect method in nuclear astrophysics are discussed.
The effects of deformation on sub-barrier fusion were first demonsrated almost fifteen years ago. Since that first analysis, it has become generally accepted that quadrupole deformation parameters ...deduced from fusion are significantly lower than those deduced from Coulomb excitation. Following a detailed analysis of the excitation function for sup 154Sm+sup 16O we find the excitation function is best fitted with deformation parameters which are consistent with Coulomb excitation data when a sufficiently complete model is used. The shape of the deduced barrier distribution strongly favors the inclusion of a positive hexadecapole moment.
The nucleus As-69 was Studied using the Ca-40(S-32,3p)As-69 reaction at a beam energy of 105 MeV. An extension of the band built on the g(9/2) orbital was observed to exhibit a band crossing at a ...rotational frequency of 0.511 MeV with an associated alignment of 7 (h) over bar. This alignment is interpreted as being due to a pair of g(9/2) neutrons. Total Routhian surface calculations have been carried out which confirm that the shape of this nucleus changes from oblate at low spin to a triaxial prolate shape at intermediate spin.