Authors & Affiliations
Russian Federation State Scientific Centre — A.I. Leipunsky Institute of Physics and Power Engineering, Obninsk, Russia
The nuclear data evaluation is performed with use of realistic covariance matrix of observable uncertainties of the experimental data. This matrix is built on the base of the model of piecewise constant energy dependence of the experimental uncertainties. The use of this model makes it possible in the process of LSM solution to go without inversion of ill-conditioned matrix with rank, equal to full number of the experimental points and to invert matrix with rank, equal to number of energy zones of the mentioned above piecewise constant function. In the frame of traditional LSM the problem of the joint processing of already known estimates and the new experimental data is considered. The algorithm for construction of the covariance matrixes of the uncertainties of the different reactions multigroup cross-sections, correlated because of the use of the same reference cross-sections in the relative measurements, is described
covariance matrix of the errors, model piecewise constant dependence, multigroup assessments sections, correlation support of section
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