Approximate Model of Neutron Resonant Scattering in a Crystal

نویسندگان

  • Arnaud Courcelle
  • John Rowlands
چکیده

In the theory of resonant scattering, the double differential cross section involves the computation of a multifold integral of a 4-point correlation function, which generalizes the traditional 2-point correlation function of Van-Hove for potential scattering. In the case of a neutron-crystal interaction, the numerical computation of these multifold integrals is cumbersome. In this paper, a new approximation is suggested. It is based on a factorization of the differential cross section into one function describing the exchange of kinetic energy between the neutron and the bound nucleus (phonons dynamic) and a function related to the nuclear scattering amplitude. This formalism is then applied to the modeling of resonant scattering of a neutron by U in a UO2 crystal lattice. Approximate Model of Neutron Resonant Scattering in a Crystal 2

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تاریخ انتشار 2008