Covariance Processing at ORNL Using PUFF-IV/ERRORJ Code Covariance Processing at ORNL Using PUFF-IV/ERRORJ Code* JEFF/EFF Meeting November 20-22, 2006 NEA, Issy-les-Moulineaux, France L. Leal *Summary of the presentations given by D. Wiarda on PUFF-IV developments

BACKGROUND PUFF Developed in 1970s to Process ENDF/B-IV Uncertainty Data (FORTRAN-IV; IBM 360/370) PUFF-II Developed to Process ENDF Data through Version V (FORTRAN-IV; IBM 3033) PUFF-III: Process ENDF Data through Version VI Added to AMPX PUFF-IV Rewritten in FORTRAN 90 to allow for a more modular design Add full processing of File 32 resonance parameter covariance data Process ENDF/B-VII uncertainty data

ENDF File Structure File 1: General information File 2: Resonance parameters File 3: Point-wise reaction cross sections File 31: Data covariance for nu(bar) File 32: Covariance data for resonance parameters File 33: Data covariance for reaction cross sections

LRU = 1 LRU = 2 Resolved resonance region LRF parameter representation LRF=1,2: Single- or Multi-Level Breit-Wigner LRF= 3: Reich Moore; LRF= 4: Adler-Adler; LRF=5,6: Not defined; LRF= 7: General R-matrix* *Not yet available in ERRORJ LRU = 2 Unresolved resonance region (very poor covariance representation) Covariance Data Storage Formats: LRU = 0 variance give but no covariance between resonances are allowed LRU = 1 entire covariance data given; LRU = 2 entire covariance data given in the compact format*

232Th Uses LCOMP=2 covariance matrix in range [1x10-5,4000] (resolved resonance range) <Mt=102;MT=102> <Mt=1;MT=1> <Mt=2;MT=2>

232Th Unresolved parameter covariances given in range [4000, 1x105 eV]. Covariance data can be given for up to 5 parameters per resonance. For 232Th fission width and competitive reaction width are not used <Mt=1;MT=1> <Mt=2;MT=2> <Mt=102;MT=102>

Create Covariance Matrices with PUFF-IV and ERRORJ PUFF-IV and NJOY/ERRORJ used to process ENDF-VII-B2 library files containing covariance data on File 31, 32 and/or File 33. Calculations were done at T=0 K for PUFF-IV and T=1.1 K for NJOY/ERRRORJ Covariance matrices with equal MAT and MT values File 32 exists Matrix exists

Covariance matrices with equal MAT and MT values File 32 exists Matrix exists

7Li, MAT=328 PUFF-IV ERRORJ 7Li File 33 content MT1=1, MAT1=328 NI: lb = 5, asymmetric MT2=851, MAT2=328: 1 NI MT1=2, MAT1=328 NC: lty = 0: 1, 4, 851 MT2=851, MAT2=328:NI, NC NI: lb = 6 MT1=4, MAT1=328 MT1=102, MAT1=328 PUFF-IV Lists all possible covariance matrices Issues warning that some cross section data are not available Skips calculation of matrices that cannot be evaluated ERRORJ Aborts since constituents of lumped reaction not found. Runs through if all reverences to lumped reaction 851 are deleted from ENDF file. Missing, (present in ENDV-VI) MT=16, MAT=328, component of MT=851 MT=16, MAT=328, component of MT=851 MT=24, MAT=328, component of MT=851

232Th, MAT=9040 PUFF-IV NJOY ERRORJ 232Th File 31 content Lists all possible covariance matrices Issues warning that some cross section data are not available Skips calculation of matrices that cannot be evaluated MT1=452, MAT1=9040 NI: lb = 1 MT2=452, MAT2=9040: 2 NI NI: lb = 5, asymmetric NI: lb = 4 MT2=452, MAT2=1380: 1 NI NI: lb = 3 MT2=452, MAT2=1381: 1 NI MT2=452, MAT2=1395: 1 NI MT2=456, MAT2=1398: 1 NI MT2=452, MAT2=1399: 1 NI 232Th File 31 content ENDF-V MAT NJOY Fails to skip over File 6 while executing groupr. Runs through once File 6 is deleted (not used for File 31, 32 or File 33 covariance calculation) ERRORJ Fails to skip over File 6 while executing groupr if processing File 31. Runs through once File 6 is deleted (not used for File 31 covariance calculation). Skips calculation of matrices that cannot be evaluated

235U, MAT=9228 PUFF-IV ERRORJ 235U File 31 content MT1=452, MAT1=9228 235U File 31 content ENDF-V MAT NI: lb = 3 MT2=452, MAT2=1380: 1 NI NI: lb = 2 MT2=452, MAT2=1381: 1 NI MT2=452, MAT2=1390: 1 NI MT2=456, MAT2=1398: 1 NI MT2=452, MAT2=1399: 1 NI PUFF-IV Lists all possible covariance matrices Issues warning that some cross section data are not available Skips calculation of matrices that cannot be evaluated ERRORJ Skips calculation of matrices that cannot be evaluated

ENDF-VII-B2 standard files Standard files contain standard reaction covariance matrices. The same matrices are expected to be present in the neutron library files. Neutron library file Standard file 6Li <MT=105;MT=105> C - <MT=2;MT=2> x 197Au <MT=1;MT=1> <MT=102;MT=102> 235U <MT=452; MT=452> <MT=456; MT=456> <MT=18;MT=18> 238U

ENDF MAT with problems in NJOY/ERRORJ 6Li ERRORJ constructs a union grid with too many energy boundaries and energy boundaries out of order. This was fixed in ERRORR. If the same fix is applied in ERRORJ, the covariance data can be calculated 23Na ENDF file contains only a File 32 and no File 33. ERRORJ only processes File 32 if a File 33 is present.

How to obtain code Puff is available from RSICC at http://www-rsicc.ornl.gov Radiation Safety Information Computational Center (RSICC) P.O. Box 2008, Oak Ridge, TN 37831-6362 USA The PUFF-IV package Code Number: P00534.