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U.S. Department of Energy
Office of Scientific and Technical Information

NJOY: a comprehensive ENDF/B processing system

Conference ·
OSTI ID:6819934
NJOY is the successor to the MINX code. It provides an efficient and accurate capability for processing ENDF/B-IV and -V data for use in fast reactor, thermal reactor, fusion reactor, shielding, and weapons analysis. NJOY produces neutron cross sections and group-to-group scattering matrices, heat production cross sections, photon production matrices, photon interaction cross sections and group-to-group matrices, delayed neutron spectra, thermal scattering cross sections and matrices, and cross-section covariances. Detailed pointwise cross sections, heating KERMA factors, thermal cross sections, and energy-to-energy thermal matrices are also available for plotting and Monte Carlo applications. NJOY currently processes all types of data on ENDF/B except for the decay chain and fission product yield files. NJOY provides output in the CCCC ISOTXS, BRKOXS, and DLAYXS formats, in DTF/ANISN format, and in a new comprehensive format called MATXS. Other important features of NJOY include free-format input, efficient binary I/O, dynamic storage allocation, an extremely modular structure, an accurate center-of-mass Gaussian integration for two-body scattering, and a flux calculator that makes it possible to compute accurate self-shielded cross sections when wide and intermediate-width resonance effects are important. NJOY is a single, integrated, efficient system that produces almost all of the basic cross sections required for multigroup methods of nuclear analysis. 3 figures, 4 tables.
Research Organization:
Los Alamos Scientific Lab., N.Mex. (USA)
DOE Contract Number:
W-7405-ENG-36
OSTI ID:
6819934
Report Number(s):
LA-UR-78-771; CONF-780334-4
Country of Publication:
United States
Language:
English