R. G. Stokstad

Measurements of the fusion of 12C + 14N and the liquid-drop limit for 26Al

Abstract A measurement of the cross section for the fusion of 14N + 12C has been made at a 14N bombarding energy of 248 MeV. The observed value of 717 ± 85 mb is significantly smaller than the value of 936 mb expected on the basis of measurements at lower energies and an entrance-channel model for the fusion process. The experimental critical angular momentum of 27.5 ± 1.7 h , however, agrees with the prediction of the rotating liquid-drop model, suggesting that we have observed the absolute maximum angular momentum which the 26Al compound nucleus can sustain.

Description and use of the Monte Carlo code LILITA. [Modeling of equilibrium decay of heavy ion reaction products]

The computer code LILITA models the equilibrium decay of the primary reaction products of heavy-ion collisions. Two major applications of the code have been developed. The first is the prediction of relative yields, energy spectra and angular distributions of evaporation residues and light particles (alphas, protons and neutrons) produced in a heavy-ion compound-nuclear reaction. The second consists of modeling the equilibrium decay of excited fragments produced in a two-body collision (such as quasi-elastic or deep inelastic scattering). The equilibrium decay of the reaction products is calculated by using the Hauser-Feshbach formula in conjunction with the Monte Carlo method, and the results are given in the laboratory system - in either singles or coincidence modes. The code can generate the results in both histogram and event-by-event formats to suit the application of the user. The approximations used in evaluating the Hauser-Feshbach formula and its use in conjunction with the Monte Carlo method are described. A description of the program input and a discussion of the event-by-event calculations are given. The processing of the event-by-event file used for coincidence calculations, either for fusion reactions or for two-body inelastic collisions is described. Comments on the parameters used for the statistical model calculations aremorexa0» given, and in the Appendix the flow diagram of the code is discussed.«xa0less