Proposal to Improve Nuclear Reactions Theory under the UNEDF

1) One of the goals of UNEDF SciDAC is to deliver optical model potentials (OMP) that leverage the UNEDF-related nuclear structure computations. The ground state transition densities are folded with realistic nuclear forces to obtain transition potentials for a coupled channel computation. Then, OMPs are fitted to S-matrix elements (or cross-sections) obtained from a coupled-channel computation using such transition potentials. In the third year it is planned to use IMAGO to fit both L-dependent and energy-dependent OMPs to S-matrix elements. 2) Statistical theories of nuclear reactions developed by Feshbach, Kerman and collaborators provide a framework for constructing energy averages of compound and pre-compound nuclear reactions. The work of Arbanas, Bertulani, Dean, Kerman, and Roche has been to construct a model based on Kawai-Kerman-McVoy (KKM) theory [1]to numerically verify a central result of KKM, namely that the energy average of the fluctuating part of the KKM T-matrix is negligibly small [2]. In year 3 of this collaboration, the validity of approximations used in the derivations of KKM cross-sections will be investigated within the same model. It is also planned to extend this model to doorway states [3], and improve statistics by parallelizing the computer code. References: [1]M. Kawai, A.K. Kerman, K.W. McVoy, "Modification of Hauser-Feshbach Calculations by Direct-Reaction Channel Coupling", Ann. of Phys. 75 (1973) 156-170 [2]G. Arbanas, C. Bertulani, D.J. Dean, A.K. Kerman, "Statistical Properties of Kawai-Kerman-McVoy T-matrix", AIP Conference Proceedings 1005 (2008) 160