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Intermediate mass fragments (IMF) and light particles emitted from the Ni-58 + Ni-58 reaction at a beam energy of 375 MeV have been studied. The fragments and light particles were measured in coincidence with 4 pi gamma-ray spectrometer. The Z=6 (C) kinetic energy spectra and the distribution of the final nuclei in coincidence with the emitted C are well described by Hauser-Feshbach calculations extended to many channels. A detailed study of C-Psi and 3 alpha-gamma correlations indicate a strong selectivity of the IMF decay. Our results indicate that the IMF can populate nuclei that are not accessible via multiple light particle (Z

The 3He(alpha,gamma)7Be reaction presently represents the largest nuclear uncertainty in the predicted solar neutrino flux and has important implications on the big bang nucleosynthesis, i.e., the production of primordial 7Li. We present here the results of an experiment using the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be ejectiles. In addition, off-beam activation and coincidence gamma-ray measurements were performed at selected energies. At energies above 1 MeV a large discrepancy compared to previous results is observed both in the absolute value and in the energy dependence of the cross section. Based on the available data and models, a robust estimate of the cross section at the astrophysical relevant energies is proposed.

The rate of the hydrogen-burning carbon-nitrogen-oxygen (CNO) cycle is controlled by the slowest process, 14N(p,γ )15O, which proceeds by capture to the ground and several excited states in 15O. Previous extrapolations for the ground state contribution di

Energy spectra and angular distributions of projectile-like fragments, ranging from {sup 7}Be to {sup 18}O, have been measured for the 120 MeV {sup 19}F+{sup 64}Ni reaction. Experimental evidence is given for the presence of two dissipative components attributed, on the basis of optimum {ital Q} values, to incomplete fusion and deep-inelastic collision mechanisms. Measured {ital Q}-value spectra show the dominance of the incomplete fusion mechanism in N and O isotopes production, while deep-inelastic collisions increase with the charge transfer. Furthermore, angular distributions and optimum {ital Q} values display larger relative contributions of incomplete fusion with respect to deep inelastic collisions for heavier isotopes of each {ital Z}. An incomplete fusion model reproduces the cross sections for most of the channels where this mechanism is prevalent. An attempt to include deep inelastic mechanisms in the same model is presented.

Mass and charge distributions for heavy residues in the reaction /sup 20/Ne+ /sup 60/Ni at 37.1 MeV/nucleon were measured by both in-beam and radioactivity ..gamma..-ray spectrometry. The general features of the experimental data are well reproduced by a massive transfer model. The heavier residues are also interpreted in the framework of a participant spectator model.

In a Comment on our analysis of measured {sup 4}He energy spectra for the composite system {sup 60}Ni ({ital E}{sup *}=75 MeV and {ital J}{sub max}=38{h bar}), Nicolis and Sarantites have reported statistical-model calculations which reproduce most of the features of the data assuming spherically symmetric parameters. This result is in disagreement with the strong deformations we have found for this compound nucleus. We show in this reply that the different conclusions concerning the magnitude of reduction in the emission barrier arise essentially from the choice of the transmission coefficients in statistical-model calculations. In particular, optical-model transmission coefficients used by Nicolis and Sarantites provide {sup 4}He energy spectra significantly softer than those obtained using transmission coefficients derived from fusion systematics adopted in our calculations. Nevertheless, even using the optical-model transmission coefficients a significant sub-barrier disagreement between data and calculations still exists, indicating important emitter deformations. A comparison between the two sets of proton transmission coefficients reveals strong differences whose influence on {sup 4}He energy spectra is discussed.