Emission of alpha particles in the interaction of 10?85 MeV protons with48,50Ti

Abstract

The excitation functions of twenty nuclear reactions induced by protons of up to 85 MeV incident upon 48Ti and S~ targets have been measured. Most of these involve the emission of one to three alpha particles. The Exciton model has been used to calculate these excitation functions. An expanded and more precise treatment of nucleon-alpha scattering has been incorporated into the model. It is presented and the implications of its predictions discussed. The agreement of experiment and calculation is very good lending support to the approach to alpha particle interactions introduced in this work.Nuclear Reactions: 48Ti(p, xnypzcO, S~ xnypze), x =0-7, y=2-6, z=0-3; measured a(E). Calculated a(E). 48Ti, 5~ enriched targets.

Analysis of59Co (?, x p y n z ?) reactions up to 170 MeV incident ? energy

“…These calculations were very successful in reproducing the large amount of existing experimental data with an accuracy comparable to that obtained in the case of nucleon induced reactions [2]. Furthermore these results were obtained using the same set of parameters as that already used in a series of calculations of cross sections of nucleon and ~-induced reactions [2][3][4][5] for describing the cascade of intranuclear interactions during which either the preequilibrium emission of fast particles or the distribution of the excitation energy among an ever increasing number of particles and holes occurs. In the many previous analyses of cr particle induced reactions, the simplifying hypothesis was made that the e-nucleus interaction could excite states whose configuration is characterized by a single exciton number.…”

“…Alpha emission processes contribute to a 5 by an amount ranging from ~15 to ~30~o and the probability of alpha survival, until its energy becomes less than Coulomb barrier, varies from ,-~35~ to ~0. The parameters entering the calculation of the cross sections are for the most part the ones already used in previous analyses of nucleon and r~-induced reactions [2][3][4][5]. Briefly we used: (a) experimental values of the Binding energies when known [22] or, when unknown, values calculated using the Myers and Swiatecki mass formula [23]; (b) pairing energies from Nemirowski and Adamchuck [24]; (c) state densities and exciton-exciton decay rates evaluated as reported in [25]; (d) semiclassical expressions for inverse cross sections, with the parameters reported in [2]; (e) decay rates for emission of nucleons and e's in the pre-equilibrium phase as reported in [26] and [8] respectively; (f) decay rates for secondary particle emission in the pre-equilibrium and in the evaporative phase as in [2].…”

Reaction mechanisms of fast neutrons on stable Mo isotopes below 21 MeV

“…For preequilibrium deuteron emission, we have adopted, as a first trial, a simple extrapolation of the Milano group method for the case of the α-particle PE emission (see e.g., [73]). The corresponding s.p.l.…”

Excitation functions for production of 46 Sc by deuteron and proton beams in nat Ti: A basis for additional monitor reactions

“…An additional experiment might bring clarification. Unfortunately the data obtained by Gadioli et al [54] in this energy region on enriched targets ( 48 Ti and 50 Ti) could not be included in this study because information on the contribution of reactions on the stable isotope 49 Ti is missing and are important.…”