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arXiv · 2210.12105

Collective enhancement in the exciton model

M. R. Mumpower·D. Nuedecker·H. Sasaki·T. Kawano·A. E. Lovell·M. W. Herman·I. Stetcu·M. Dupuis
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Abstract

The pre-equilibrium reaction mechanism is considered in the context of the exciton model. A modification to the one-particle one-hole state density is studied which can be interpreted as a collective enhancement. The magnitude of the collective enhancement is set by simulating the Lawrence Livermore National Laboratory (LLNL) pulsed-spheres neutron-leakage spectra. The impact of the collective enhancement is explored in the context of the highly deformed actinide, 239-Pu. A consequence of this enhancement is the removal of fictitious levels in the Distorted-Wave Born Approximation often used in modern nuclear reaction codes.

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M. R. Mumpower, D. Nuedecker, H. Sasaki, T. Kawano, A. E. Lovell, M. W. Herman, I. Stetcu, M. Dupuis. 2022-10-21. Collective enhancement in the exciton model. https://doi.org/10.1103/physrevc.107.034606

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