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7-N - 15 LANL EVAL-SEP83 E.ARTHUR,P.YOUNG,G.HALE
DIST-JAN09 20090105
----JEFF-311 MATERIAL 728
-----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 *************************
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** Original data taken from: JEFF-3.0 **
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***************************** JEFF-3.0 *************************
DATA TAKEN FROM :- ENDF/B-VI.3 (DIST-JUN90)
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ENDF/B-VI MODIFICATIONS
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REVISED SPRING, SUMMER OF 1983 BY YOUNG AND ARTHUR TO INCLUDE
IMPROVED OPTICAL MODEL PARAMETERS, UPDATED LEVEL SCHEMES, IM-
PROVED VERSION OF GNASH, AND MORE CAREFUL TREATMENT OF
LEVEL DENSITY PARAMETERS. SEE ARTHUR AND YOUNG ARTICLES IN THE
OCT.1982 - MAR.1983 T-2 PROGRESS REPORT (LA-9841-PR, 1983)
FOR DETAILS. SECTIONS UPDATED ARE,
MF= 3/ MT=2,4,16,22,28,51-57,91,103,104,105,107
MF=13/ MT=4,16,22,28,103,104,105,107
MF=14/ MT=22,28
MF=15/ MT=4,16,22,28,103,104,105,107
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ENDF/B-V DESCRIPTION
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THE LACK OF EXPERIMENTAL DATA, WITH THE EXCEPTION OF TOTAL
CROSS SECTION MEASUREMENTS,LED US TO OBTAIN CROSS SECTIONS WITH
A VARIETY OF NUCLEAR MODEL CODES. WE USED AN ENERGY DEPENDENT
R MATRIX ANALYSIS TO FIT THE TOTAL CROSS SECTION DATA OF
ZE71 FOR NEUTRON ENERGIES FROM 0.8 TO 5.4 MEV. AS A STARTING
POINT WE USED THE LEVEL SCHEME REPORTED IN ZE71. ALSO USED
IN THE R MATRIX ANALYSIS WERE THE ELASTIC ANGULAR DISTRIBU-
TIONS OF SI62 AND ZE71 IN THE ENERGY RANGE FROM 1.9 TO 3.64
MEV. THE PARAMETERS OF THE R-MATRIX ANALYSIS WERE THEN USED
TO GENERATE CROSS SECTIONS AND TO DETERMINE LEGENDRE COEFFI-
CIENTS IN THE RANGE FROM 1.0E-05 EV TO 5.4 MEV. IN THE ENERGY
REGION FROM 6 TO 20 MEV WE USED TWO STATISTICAL MODEL CODES TO
GENERATE CROSS SECTIONS. WITH THE FIRST,COMNUC, WE COMPUTED
THE ANGULAR DISTRIBUTIONS OF ELASTICALLY SCATTERED NEUTRONS.
THE LEGENDRE COEFFICIENTS OBTAINED WERE THEN JOINED SMOOTHLY
WITH THOSE FROM THE R-MATRIX ANALYSIS. WE ALSO OBTAINED
ANGULAR DISTRIBUTIONS OF NEUTRONS LEADING TO THE FIRST SEVEN
EXCITED STATES OF N15. TO GENERATE NEUTRON TRANSMISSION
COEFFICIENTS FOR THIS PART OF THE ANALYSIS WE USED THE GLOBAL
OPTICAL MODEL PARAMETERS OF WILMORE AND HODGSON AS REPORTED BY
PE74, AND ADJUSTED THEM TO GIVE GOOD AGREEMENT WITH THE
MEASURED TOTAL CROSS SECTION. THE GENERATION OF CAPTURE,
INELASTIC, AND NON ELASTIC CROSS SECTIONS AS WELL AS
NEUTRON,GAMMA-RAY, AND CHARGED-PARTICLE SPECTRA WAS DONE WITH
THE STATISTICAL MODEL CODE,GNASH. THIS NEWLY DEVELOPED CODE IS
BASED LARGELY ON THE STATISTICAL MODEL FORMALISM OF UH71.
AGAIN NEUTRON TRANSMISSION COEFFICIENTS WERE BASED ON THE
OPTICAL MODEL PARAMETERS OF WILMORE AND HODGSON. TRANSMISSION
COEFFICIENTS WERE GENERATED FOR PROTONS,DEUTERONS, AND
HE4, WITH THE APPROPRIATE GLOBAL FORMS REPORTED IN PE74. FOR
TRITONS WE USED THE GLOBAL PARAMETERS FOR HE3 REPORTED IN PE74
SINCE THESE WERE CONSISTENT WITH TRITON OPTICAL MODEL
PARAMETERS FOR INDIVIDUAL LIGHT NUCLEI AS COMPILED BY PE74.
THE GILBERT-CAMERON LEVEL DENSITY MODEL WAS USED WITH STANDARD
VALUES FOR LEVEL DENSITY PARAMETERS (GI64). TO ACCOUNT FOR
DIRECT AND SEMI-DIRECT PROCESSES WE USED THE PREEQUILIBRIUM
MODEL OF BLANN AND CLINE (CL71) AND ASSUMED A TEN PERCENT
PREEQUILIBRIUM FRACTION.
MF=2 --- RESONANCE PARAMETERS ---
MT=151 EFFECTIVE SCATTERING RADIUS = 0.592916E-12 CM
MF=3 --- SMOOTH CROSS SECTIONS ---
THE 2200 M/S CROSS SECTIONS ARE
MT= 1 SIGMA = 4.4185 BARNS
MT= 2 SIGMA = 4.418 BARNS
MT=102 SIGMA = 24.0E-06 BARNS
MT=1 TOTAL CROSS SECTION
FROM 1.0E-05 EV TO 5.4 MEV TOTAL CROSS SECTION VALUES ARE
BASED ON THE R-MATRIX ANALYSIS DESCRIBED ABOVE. FROM 5.5
TO 20 MEV THE EVALUATED CROSS SECTION IS BASED ON THE
SMOOTHED RESULTS OF ZE71.
MT=2 ELASTIC SCATTERING CROSS SECTION
ZERO TO 20 MEV, SUBTRACTED EVALUATED NON-ELASTIC FROM TOTAL
TO GIVE ELASTIC CROSS SECTION
MT=3 SUM OF ALL CROSS SECTIONS EXCEPT ELASTIC
MT=4 SUM OF MT=51-57, 91 CROSS SECTIONS
MT=16 (N,2N) CROSS SECTION
BASED ON SMOOTH CURVE DRAWN THROUGH RESULTS OF THE
STATISTICAL MODEL CALCULATIONS DESCRIBED BEFORE
MT=22 (N,N ALPHA) CROSS SECTION
BASED ON SMOOTHED RESULTS OF STATISTICAL MODEL CALCULATION
MT=28 (N,NP) CROSS SECTION
BASED ON SMOOTHED RESULTS OF STATISTICAL MODEL CALCULATION
MT=51-57 INELASTIC CROSS SECTION TO DISCRETE STATES
MT=51 Q=-5.27 MEV MT=55 Q=-7.301 MEV
MT=52 Q=-5.299MEV MT=56 Q=-7.566 MEV
MT=53 Q=-6.324MEV MT=57 Q=-8.313 MEV
MT=54 Q=-7.155MEV
MT=91 (N,N) TO CONTINUUM
CONTINUUM DEFINED TO BEGIN AT 0.1 MEV ABOVE LAST N-15
DISCRETE LEVEL INCLUDED IN CALCULATION, I.E. CONTINUUM
BEGINS AT 8.413 MEV
MT=102 (N,GAMMA) CROSS SECTION
ZERO TO 0.010 MEV, 1/V FROM 24.0E-06 BARNS AT THERMAL
6 TO 20 MEV CALCULATED FROM STATISTICAL MODEL WITH AXEL
(AX62) GIANT DIPOLE RESONANCE APPROXIMATION FOR GAMMA-
RAY TRANSMISSION COEFFICIENTS
.010 TO 6 MEV, CROSS SECTION BASED ON SMOOTHED CURVE FROM
REGION WHERE 1/V DEPENDENCE ENDS TO REGION WHERE
CALCULATED VALUES BEGIN.
MT=103 SUM OF MT= 700,701, AND 718 CROSS SECTIONS
MT=104 SUM OF MT= 720,721,722,AND 738 CROSS SECTIONS
MT=105 SUM OF MT=740,741, AND 758 CROSS SECTIONS
MT=107 SUM OF MT= 780-785 AND 798 CROSS SECTIONS
MT=700,701 (N,P) CROSS SECTION TO C15 GROUND AND FIRST EXCITED
STATES
MT=700 Q=-8.990 MEV EX=0. MEV
701 Q=-9.737 EX=.747
MT=738 (N,D) TO CONTINUUM STATES OF C14
CONTINUUM DEFINED TO BEGIN AT 0.85 MEV, JUST ABOVE FIRST
EXCITED STATE
MT=720-722 (N,D) CROSS SECTION TO C14 GROUND,FIRST,AND SECOND
EXCITED STATES
MT=720 Q=-7.984 MEV EX=0. MEV
MT=721 Q=-14.079 EX=6.095
MT=722 Q=-14.567 EX=6.583
MT=740-742 (N,T) CROSS SECTION TO C13 GROUND,FIRST,AND SECOND
EXCITED STATES
MT=738 (N,D) TO CONTINUUM STATES OF C15
CONTINUUM DEFINED TO BEGIN AT 6.681 MEV, JUST ABOVE SECOND
EXCITED LEVEL IN C14
MT=740 Q=-9.902 MEV EX=0. MEV
741 Q=-12.992 3.09
742 -13.586 3.684
MT=780-785 (N,ALPHA) CROSS SECTION TO B12 GROUND AND FIRST
FIVE EXCITED STATES
MT=780 Q=-7.623 MEV EX=0. MEV
781 -8.576 .953
782 -9.297 1.674
783 -10.244 2.621
784 -10.343 2.72
785 -11.013 3.39
MT=758 (N,T) TO CONTINUUM STATES OF C13
CONTINUUM BEGINS AT 3.784 MEV, ABOVE SECOND EXCITED LEVEL
IN C13
MT=798 (N,ALPHA) TO CONTINUUM STATES OF B12
CONTINUUM BEGINS AT 3.49 MEV, JUST ABOVE FIFTH EXCITED
STATE IN B12
MF=4 --- SECONDARY NEUTRON AND CHARGED PARTICLE ANGULAR
DISTRIBUTIONS
MT=2 ELASTIC ANGULAR DISTRIBUTIONS
ZERO TO 5.4 MEV BASED ON RESULTS OBTAINED FROM R MATRIX
THEORY ANALYSIS
6 TO 20 MEV BASED ON OPTICAL MODEL CALCULATION
MT=16 ANGULAR DISTRIBUTION FOR (N,2N) REACTION
IN THE ABSENCE OF DATA ISOTROPY IN THE LAB SYSTEM IS ASSUMED
MT=22 ANGULAR DISTRIBUTION OF NEUTRONS FROM (N,NALPHA)
REACTION ASSUED ISOTROPIC IN THE LAB SYSTEM
MT=28 ANGULAR DISTRIBUTION OF NEUTRONS FROM (N,NP) REACTION
ASSUMED ISOTROPIC IN THE LAB SYSTEM
MT=51-57 ANGULAR DISTRIBUTION CALCULATED USING HAUSER-
FESHBACH THEORY
MT=718 ANGULAR DISTRIBUTION OF PROTONS FROM (N,P) REACTION
ASSUMED ISOTROPIC IN THE LAB
MT=719 ANGULAR DISTRIBUTION OF PROTONS FROM (N,NP) ASSUMED
ISOTROPIC IN THE LAB
MT=738 ANGULAR DISTRIBUTION OF DEUTRONS FROM (N,D) ASSUMED
ISOTROPIC IN THE LAB
MT=758 ANGULAR DISTRIBUTION OF TRITONS FROM (N,T) REACTION
ASSUMED ISOTROPIC IN THE LAB
MT=798 ANGULAR DISTRIBUTION OF ALPHA S FROM (N,ALPHA) REACTION
ASSUMED ISOTROPIC IN THE LAB SYSTEM
MT=799 ANGULAR DISTRIBUTION OF ALPHAS FROM (N,N ALPHA) REACTION
ASSUMED ISOTROPIC IN THE LAB
MF=5---ENERGY DISTRIBUTION OF SECONDARY NEUTRONS AND CHARGED
PARTICLES---
MT=16,22,28,91,718,758,AND 798 CALCULATED WITH STATISTICAL
MODEL CODE
MT=719 USED FOR PROTON SPECTRA FROM (N,NP) REACTION
MT=799 USED FOR ALPHA SPECTRA FROM (N,N ALPHA) REACTION
MF=13 --- PHOTON PRODUCTION CROSS SECTIONS---
MT=4,16,103,104,105,AND 107 INCLUDE BOTH DISCRETE AND
CONTINUUM CONTRIBUTIONS AND WERE GENERATED WITH THE
STATISTICAL MODEL CALCULATION
MF=14--- PHOTON ANGULAR DISTRIBUTIONS---
MT= 4 (N,N) TO N15, ALL ISOTROPIC
MT=103 (N,P) TO C15 ALL ISOTROPIC
MT=104 (N,D) TO C14, ALL ISOTROPIC
MT=105 (N,T) TO C13, ALL ISOTROPIC
MT=107 (N,ALPHA) TO B12, ALL ISOTROPIC
MT=16 (N,2N GAMMA) TO N14, ALL ISOTROPIC
MF=15 --- ENERGY DISTRIBUTION OF SECOND PHOTON ---
MT=4,16,103,104,105,107 GENERATED USING STATISTICAL MODEL
-----REFERENCES-----
AJ70 F.AJZENBERG-SELOVE, NUCL.PHYS.A152,1 (1973)
AJ71 F.AJZENBERG-SELOVE,NUCL.PHYS. A166,1 (1971)
AX62 L.P.AXEL, PHYS.REV. 126,671 (1972)
CL71 C.K.CLINE AND M.BLANN,NUCL.PHYS.A172,225 (1971)
FE67 P.FESSENDEN AND D.R.MAXSON,PHYS.REV.158,948 (1967)
GI65 A.GILBERT AND A.G.L.CAMERON,CAN.J. OF PHYS.43,1446 (1965)
PE74 C.M.PEREY AND F.G.PEREY,ATOMIC AND NUCL. DATA TABLES 13,293
(1974)
SI62 C.P.SIKKEMA NUCL.PHYS. 32,470 (1962)
U71 M.UHL ACTA PHYSICA AUSTRIA 31,245 (1971)
ZE71 B.ZEITNITZ ET AL.,NUCL.PHYS.A166,443 (1971)
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