Speaker: Joseph N. Ginocchio (T-16, LANL)

R-Matrix Theory and Nuclear Applications

The mathematical structure of R-matrix theory and applications to light nuclear cross sections are discussed. The R-matrix analysis of experimental data on reactions like 7Li(p,alpha), 7Be(n,p) and 6Li(d,alpha), leading to the 8Be intermediate nuclear state, will be described. 4029 data points up to an excitation energy of 23 MeV are fitted with 94 parameters. The resonance structure of 8Be is deduced. The R-matrix and logarithmic derivative are defined. Not only can these be obtained from experimental data, but also from Green's function Monte Carlo (GFMC) microscopic calculations. Results of GFMC calculations for alpha n elastic scattering will be shown. Both GFMC calculations and mathematical r-matrix theory to solve non-linear differential equations are future thrusts.