Coupled-channels Neutron Reactions

When?

Tuesday 17 May 2011, 14:00

Where?

13 BB 04

Open to:

Staff, Students

Speaker:

Ian Thompson, Livermore National Laboratory

Microscopic calculations of the reaction cross-section for nucleon-nucleus scattering have been performed by explicitly coupling the elastic channel to all the particle-hole (p-h) excitation states in the target and to all relevant pickup channels. The results of such calculations were compared to predictions of a well-established optical potential and with experimental data, reaching very good agreement. Couplings between inelastic states were found to be not significant, while the inclusion of couplings to pickup channels was an important contribution to the absorption. For the first time, calculations of excitations account for all of the observed reaction cross-sections, at least for incident energies above 10 MeV.

These channel couplings should generate all the imaginary components of the neutron optical potential, which summarizes the overall effects of non-elastic channels on the elastic wave function. Strictly, this optical potential is non-local, and energy and L-dependent. This dependence is shown, along with equivalent local potentials.

Ian Thompson Presentation (5989.59KB - Requires Adobe Reader)