Formalism for neutron cross section covariances in the resonance region using kernel approximation

Oblozinsky, P. ; Cho,Y-S. ; Matoon,C.M. ; Mughabghab,S.F.

Brookhaven National Laboratory

关键词: Potential Scattering;    Elastic Scattering;    Approximations;    Capture;    Scattering;   

DOI  :  10.2172/1013469
RP-ID  :  BNL--91287-2010
RP-ID  :  DE-AC02-98CH10886
RP-ID  :  1013469

美国|英语

来源: UNT Digital Library

【 摘 要 】

We describe analytical formalism for estimating neutron radiative capture and elastic scattering cross section covariances in the resolved resonance region. We use capture and scattering kernels as the starting point and show how to get average cross sections in broader energy bins, derive analytical expressions for cross section sensitivities, and deduce cross section covariances from the resonance parameter uncertainties in the recently published Atlas of Neutron Resonances. The formalism elucidates the role of resonance parameter correlations which become important if several strong resonances are located in one energy group. Importance of potential scattering uncertainty as well as correlation between potential scattering and resonance scattering is also examined. Practical application of the formalism is illustrated on {sup 55}Mn(n,{gamma}) and {sup 55}Mn(n,el).