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11-Na- 23 NEA EVAL-APR99 E. Fort et al.
DIST-JAN09 20090105
----JEFF-311 MATERIAL 1125
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
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** Original data taken from: JEFF-3.1 **
** **
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***************************** JEFF-3.1 *************************
** **
** Original data taken from: JEFF-3.0 **
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***************************** JEFF-3.0 ***********************
DATA TAKEN FROM :- JEF-2.2 (DIST-JAN92)
Modifications by E. Fort et al. (see comments below)
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THIS IS NOT AN EVALUATION IN THE CLASSICAL SENSE. THE ORIGINAL
JEF-2 EVALUATION (EVAL MARS 87 BY H. YAMAKOSHI WHICH, IN TURN WAS
ESSENTIALY BASED ON AN "OLD" AMERICAN WORK.) WAS DEMONSTRATED, BY
THE EXTENSIVE VALIDATION WORK [1] TO BE OF INSUFFICIENT QUALITY,
IN SUCH A WAY THAT THE RESULT OF THE GENERAL ADJUSTMENT COULD BE
QUESTIONNED (LINEARITY CONDITION). THEN, IT WAS A NECESSITY TO
INTRODUCE IN THE ADJUSTEMENT "A PRIORI" DATA OF BETTER QUALITY.
IN THIS CONTEXT THE BEST CHOICE OF DATA WAS REPRESENTED BY A
WORK BY KOPECKY, SHELLEY, MARTEN AND H. WEIGMAN PRESENTED AT THE
TRIESTE CONFERENCE [II]. IT IS THIS CHOICE WHICH IS PROPOSED TO
THE JEFF PROJECT.
THE AUTHORS OF REFERENCE [II] HAVE ANALYSED SIMULTANEOUSLY
INELASTIC CROSS SECTION DATA OBTAINED AT GEEL [III] AND THE TOTAL
CROSS SECTION DATA OBTAINED AT ORELA [IV]. THE ANALYSIS HAS BEEN
PERFORMED USING SAMMY CODE AND R MATRIX FORMALISM IN THE
REICH-MOORE APPROXIMATION WITH TWO ELASTIC CHANNELS AND TWO
INELASTIC CHANNELS FOR EVERY GIVEN RESONANCE. THE QUALITY OF THE
FIT BETWEEN THE INELASTIC THRESHOLD AND 2.0 MEV IS EXCELLENT AND
WAS OBTAINED BY USING A SINGLE SET OF RESONANCE PARAMETERS.
THIS WAS A CONVINCING ISSUE ENABLING US TO PROPOSE THIS SET
OF DATA AS A STARTING VERSION OF AN EVALUATION TO BE COMPLETED IN
THE FUTURE BY USING THE CLASSICAL RULES.
BELOW 450 KEV (INELASTIC THRESHOLD) THE DATA ARE UNCHANGED WITH
RESPECT TO JEF2 EVALUATION.
ABOVE 2 MEV, THE JEF2 DATA WERE SCALED BY 0.69 FOR WHAT CONCERNS
THE INELASTIC CROSS SECTION AND BY 1.32 FOR WHAT CONCERNS THE
ELASTIC CROSS SECTION. THESE CORRECTIVE FACTORS WERE DETERMINED
IN ORDER TO MATCH WITH KOPECKY'S DATA AT LOWER ENERGY. THEY ARE
ALSO CONSISTENT WITH THE VALIDATION INDICATION.
THE PROPOSED DATA SET HAS BEEN SUCCESSFULLY TESTED AGAINST
INTEGRAL DATA. WITH RESPECT TO THE JEF2.2 EVALUATION, THERMAL
CONSTANTS AND RESONANCE CAPTURE INTEGRAL ARE UNCHANGED AND THE
CAPTURE CROSS SECTION ON THE FULL ENERGIE RANGE ALSO.
[I] E. FORT, W. ASSAL, A,AVERY, PBLAISE, J.C. BOSQ, S. CATHLAU
C. DEAN, J.P. FINK, G. RIMPAULT, J. ROWLANDS, P. SMITH,
M. SALVARORES, R.SOULE, V.ZAMMIT.
JEF2 VALIDATION. PART 1. GENERAL PURPOSE FILE. JEF/DOC
[II] S. KOPECKY, R. SHELLEY, H. MARTEN AND H. WEIGMAN.
CONFERENCE PROCEEDINGS. NUCLEAR DATA FOR SCIENCE AND
TECHNOLOGY. TRIESTE MAY 1987.
[III] H. MARTEN, J. WARTENA AND H. WEIGMAN
IRMM REPORT GE/R/ND/02/94 1994
[IV] D.C. LARSON
PRIVATE COMUNICATION TO THE AUTHORS OF REFERENCE [II]
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* JEF-2 DATA WERE TAKEN FROM JENDL-3
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* 2-FEB-90: MODIFICATIONS TO THIS FILE IN THE ENERGY RANGE
* 1.0E-5 EV TO 700 KEV IS PROPOSED BY M. MOXON AND
* M. SOWERBY, HARWELL, AND WILL BE INCLUDED IN THE
* NEAR FUTURE.
******** HYSTORY OF JE2
87-03 NEW EVALUATION WAS MADE FOR JENDL-3.
89-08 THE DATA FOR MF=15,MT=102 MODIFIED.
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MF=1 GENERAL INFORMATION
MT=451 DESCRIPTIVE DATA AND DICTIONARY
MF=2 RESONANCE PARAMETERS
MT=151 RESOLVED RESONANCE PARAMETERS
RESOLVED PARAMETERS FOR MLBW FORMULA WERE GIVEN IN
THE ENERGY REGION FROM 1.0E-5 EV TO 350 KEV.
PARAMETERS WERE MAINLY TAKEN FROM THE RECOMMENDED DATA OF BNL
/1/, AND THE DATA FOR SOME LEVELS WERE MODIFIED SO THAT THE
CALCULATED TOTAL CROSS SECTIONS FOR NA-23 WERE FITTED TO THE
EXPERIMENTAL DATA.
THE SCATTERING RADIUS WAS ASSUMED TO BE 5.2 FERMI.
CALCULATED 2200 M/SEC CROSS SECTIONS AND RESONANCE INTEGRALS
ARE AS FOLLOWS:
2200 M/S CROSS SECTION(B) RES. INTEGRAL(B)
ELASTIC 3.024
CAPTURE 0.531 0.3122
TOTAL 3.555
MF=3 NEUTRON CROSS SECTIONS
BELOW 350 KEV, BACKGROUND CROSS SECTION WAS GIVEN FOR
THE TOTAL AND ELASTIC SCATTERING CROSS SECTIONS.
THE CROSS-SECTION DATA ARE REPRODUCED FROM THE EVALUATED
RESOLVED RESONANCE PARAMETERS WITH MLBW FORMULA.
ABOVE 350 KEV, THE TOTAL AND PARTIAL CROSS SECTIONS WERE GIVEN
POINTWISE.
MT=1 TOTAL
IN THE ENERGIES BETWEEN 350 KEV AND 14 MEV, EVALUATED BASED ON
THE EXPERIMENTAL DATA OF CIERJACKS/2/ IN TRACING THEIR FINE
STRUCTURES. ABOVE 14 MEV, BASED ON THE EXPERIMENTAL DATA OF
LANGSFORD/3/, STOLER/4/ AND LARSON/5/.
MT=2 ELASTIC SCATTERING
OBTAINED BY SUBTRACTING THE SUM OF THE PARTIAL CROSS SECTIONS
FROM THE TOTAL CROSS SECTION.
MT=4, 51-77, 91 INELASTIC SCATTERING
BELOW 5 MEV, THE INELASTIC SCATTERING CROSS SECTION TO THE 1ST
LEVEL(MT=51) WAS EVALUATED BASED ON THE EXPERIMENTAL DATA OF
TOWLE AND GILBOY/6/, CHRIEN AND SMITH/7/, AND LIND AND DAT/8/.
BELOW 5 MEV, THE INELASTIC SCATTERING CROSS SECTION TO THE 2ND
AND 3RD LEVEL(MT=52, 53) WAS EVALUATED BASED ON THE EXPERIMENTAL
DATA OF FREEMAN AND MONTAGUE/9/, LIND AND DAT/8/, AND TOWLE AND
OWENS/10/. FOR THE INELASTIC SCATTERING CROSS SECTIONS TO THE
1ST TO 3RD LEVELS ABOVE 5 MEV AND THE OTHER INELASTIC SCATTERING
DATA, OPTICAL AND STATISTICAL MODEL CALCULATIONS WERE MADE WITH
THE CASTHY CODE/11/, TAKING ACCOUNT OF THE CONTRIBUTION FROM THE
COMPETING PROCESSES. THE DIRECT COMPONENT WAS CALCULATED WITH
WITH THE DWUCK CODE/12/ FOR FIVE LOWEST LEVELS. THE DEFORMATION
PARAMETERS WERE ESTIMATED BASED ON A WEAK COUPLING MODEL.
THE OPTICAL POTENTIAL PARAMETERS USED ARE:
V = 46.0 - 0.25*EN, VSO = 6.0 (MEV)
WS = 14.0 - 0.2*EN, WV = 0.125*EN (MEV)
R = 1.286, RS = 1.39, RSO = 1.07 (FM)
A = 0.62, ASO = 0.62, B = 0.7 (FM)
THE LEVEL DATA USED IN THE ABOVE TWO CALCULATIONS WERE TAKEN
FROM REF./13/ AS FOLLOWS:
MT LEVEL ENERGY(MEV) SPIN-PARITY
0.0 3/2+
51 0.4399 5/2+
52 2.0764 7/2+
53 2.3909 1/2+
54 2.6398 1/2-
55 2.7037 9/2+
56 2.9824 3/2+
57 3.6783 3/2-
58 3.8480 5/2-
59 3.9147 5/2+
60 4.4320 1/2+
61 4.7756 7/2+
62 5.3800 3/2+
63 5.5360 11/2+
64 5.7410 3/2+
65 5.7660 5/2+
66 5.9310 1/2-
67 5.9670 3/2-
68 6.0430 1/2-
69 6.1170 11/2+
70 6.1910 11/2+
71 6.2360 13/2+
72 6.3080 1/2+
73 6.3506 9/2-
74 6.5770 5/2+
75 6.6170 9/2+
76 6.7340 3/2+
77 6.8680 5/2+
LEVELS ABOVE 6.9 MEV WERE ASSUMED TO BE OVERLAPPING.
MT=16 (N,2N)
MAINLY BASED ON THE EXPERIMENTAL DATA OF ADAMSKI/14/.
MT=22 (N,NA)
CALCULATED WITH THE GNASH CODE/15/ AND NORMALIZED TO
THE EXPERIMENTAL DATA OF WOELFER/16/ AT 16.4 MEV.
MT=28 (N,NP)
CALCULATED WITH THE GNASH CODE/15/.
MT=102 CAPTURE
CALCULATED WITH THE CASTHY CODE/11/ AND NORMALIZED TO 0.3 MB
AT 500 KEV.
MT=103 (N,P)
BELOW 10 MEV, BASED ON THE EXPERIMENTAL DATA/17,18/.
ABOVE 10 MEV, CALCULATED WITH THE GNASH CODE/15/ AND NORMALIZ-
ED TO CONNECT SMOOTHLY WITH THE DATA BELOW 10 MEV.
MT=107 (N,A)
BELOW 12 MEV, BASED ON THE EXPERIMENTAL DATA/17,18/.
ABOVE 12 MEV, CALCULATED WITH THE GNASH CODE/15/ AND NORMALIZ-
ED TO CONNECT SMOOTHLY WITH THE DATA BELOW 10 MEV.
MT=251 MU-BAR
CALCULATED WITH THE OPTICAL MODEL.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2
CALCULATED WITH THE CASTHY CODE/11/.
MT=51-77
CALCULATED WITH THE CASTHY CODE/11/ AND THE DWUCK CODE/7/.
MT=91
CALCULATED WITH THE CASTHY CODE/11/.
MT=16, 22, 28
ISOTROPIC IN THE LABORATORY SYSTEM.
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=16, 22, 28, 91
CALCULATED WITH THE GNASH CODE/15/.
MF=12 PHOTON PRODUCTION MULTIPLICITIES
MT=102
CALCULATED WITH THE GNASH CODE/15/ AND MODIFIED AT
THERMAL BASED ON THE EXPERIMENTAL DATA OF MAERKER/19/.
MF=13 PHOTON PRODUCTION CROSS SECTIONS
MT=3
CALCULATED WITH THE GNASH CODE/15/.
MF=14 PHOTON ANGULAR DISTRIBUTIONS
MT=3, 102
ASSUMED TO BE ISOTROPIC IN THE LABORATORY SYSTEM.
MF=15 CONTINUOUS PHOTON ENERGY SPECTRA
MT=3
CALCULATED WITH THE GNASH CODE/15/.
MT=102
CALCULATED WITH THE GNASH CODE/15/ AND MODIFIED AT
THERMAL BASED ON THE EXPERIMENTAL DATA OF MAERKER/19/.
REFERENCES
1) MUGHABGHAB S.F. AND GARBER D.I. :"NEUTRON CROSS SECTIONS",
VOL. 1, PART B (1984).
2) CIERJACKS S. ET AL. : KFK-1000 (1969).
3) LANGSFORD A. ET AL. : 1965 ANTWERP CONF. 529 (1965).
4) STOLER P. ET AL. : 1971 KNOXVILLE CONF. VOL.1, 311 (1971).
5) LARSON D.C. ET AL. : ORNL-TM-5614 (1976).
6) TOWLE J.H. AND GILBOY W.B. : NUCL. PHYS. 32, 610 (1962).
7) CHRIEN J.P. AND SMITH A.B. : NUCL. SCI. ENG. 26, 500 (1966).
8) LIND D.A. AND DAY R.B. : ANN. PHYS. 12, 485 (1961).
9) FREEMAN J.M. AND MONTAGUE J.H. : NUCL. PHYS. 9, 181 (1958).
10) TOWLE J.H. AND OWENS R.O. : NUCL. PHYS. A100, 257 (1967).
11) IGARASI S. : J. NUCL. SCI. TECH. 12, 67 (1975).
12) KUNZ P.D. : UNPUBLISHED.
13) ENSDF(EVALUATED NUCLEAR STRUCTURE DATA FILE)
14) ADAMSKI L. ET AL. : ANNA. NUCL. ENER. 7, 397 (1980).
15) YOUNG P.G. AND ARTHUR E.D. : LA-6947 (1977).
16) WOELFER G. ET AL. : Z. PHYS. 194, 75 (1966).
17) WILLIAMSON C.F. : PHYS. REV. 122, 1877 (1961).
18) BASS R. ET AL. : 1965 ANTWERP CONF. 495 (1966).
19) MAERKER R.E. : ORNL-TM-5203 (1976).
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