1. 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

2. 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

3. 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

4. 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 = variance give but no covariance between resonances are allowed
LRU = entire covariance data given;
LRU = entire covariance data given in the compact format*

5. 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>

6. 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>

7. 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

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

9. 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

10. 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

11. 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

12. 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

13. 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.

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