Nucleon-induced reactions at intermediate energies: New data at96MeVand theoretical status

Abstract

Double-differential cross sections for light charged particle production (up to A = 4) were measured in 96 MeV neutron-induced reactions, at TSL laboratory cyclotron in Uppsala (Sweden). Measurements for three targets, Fe, Pb, and U, were performed using two independent devices, SCANDAL and MEDLEY. The data were recorded with low energy thresholds and for a wide angular range (20 − 160 degrees). The normalization procedure used to extract the cross sections is based on the np elastic scattering reaction that we measured and for which we present experimental results. A good control of the systematic uncertainties affecting the results is achieved. Calculations using the exciton model are reported. Two different theoretical approches proposed to improve its predictive power regarding the complex particle emission are tested. The capabilities of each approach is illustrated by comparison with the 96 MeV data that we measured, and with other experimental results available in the literature.

Measurement and model analysis of(n,xα)cross sections for Cr, Fe,59Co, andKunieda1, Haight2, Kawano3 et al. 2012Phys. Rev. C25030View full textAdd to dashboardCite

“…Low energy alpha-particles were measured well with the thin samples and the good performance of the low-pressure gas proportional counters. This latter capability differentiates these measurements from those of other laboratories as reported in the literature [14,15,20] for the measurement of the total alpha-particle production. As this report focuses on preequilibrium reactions, the spectra measured below 15-MeV incident neutron energy will be discussed in terms of the statistical nuclear reaction model in a subsequent publication [21].…”

“…At other laboratories, partial alpha-particle spectra that concentrate on the pre-equilibrium part of the spectra were measured in detail at principally at 62.7 MeV, and with larger statistical errors, at energies from 25 to 53 MeV on iron and cobalt [14]. Also a detailed monoenergetic measurement on iron was made at 96 MeV [15].…”

Production of energetic light fragments in extensions of the CEM and LAQGSM event generators of the Monte Carlo transport code MCNP6

“…As is frequently done (see e.g., Refs. [65,67]), the values of γ j are taken from fitting the theoretical preequilibrium spectra to the experimental ones. In CEM03.03F, to improve the description of preequilibrium complex-particle emission, we estimate γ j by multiplying the estimate provided by Eq.…”

“…γ j is the probability that the proper number of particle excitons will coalesce to form a type j fragment (also called γ β in a number of earlier publications; see, e.g., Refs. [65][66][67]). …”

Neutron-induced light-ion production from Fe, Pb and U at 96 MeV

“…This interest has been manifested in part by extensive experimental campaigns, like the one carried out by several laboratories in Europe within the framework of HINDAS [2]. The results presented here are part of this program and concern double-differential cross sections for light-ion emission (up to A=4) induced by 96 MeV neutrons on nat Fe, nat Pb and nat U [3].…”