Extended covariance data formats for the ENDF/B-VI differential data evaluation

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6762155

Peelle, R W; Muir, D W

The ENDF/B-V included cross section covariance data, but covariances could not be encoded for all the important data types. New ENDF-6 covariance formats are outlined including those for cross-file (MF) covariances, resonance parameters over the whole range, and secondary energy and angle distributions. One ''late entry'' format encodes covariance data for cross sections that are output from model or fitting codes in terms of the model parameter covariance matrix and the tabulated derivatives of cross sections with respect to the model parameters. Another new format yields multigroup cross section variances that increase as the group width decreases. When evaluators use the new formats, the files can be processed and used for improved uncertainty propagation and data combination. 22 refs.

• Research Organization: Oak Ridge National Lab., TN (USA); Los Alamos National Lab., NM (USA)
• DOE Contract Number: AC05-84OR21400; W-7405-ENG-36
• OSTI ID: 6762155
• Report Number(s): CONF-8809156-1; ON: DE89000649
• Country of Publication: United States
• Language: English

Related Subjects

651000* -- Nuclear Physics
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CROSS SECTIONS
DATA COVARIANCES
NUCLEAR DATA COLLECTIONS