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97-Bk-249 JAERI EVAL-MAR85 Y.KIKUCHI AND T.NAKAGAWA
JAERI-M 85-138 DIST-JAN09 20090105
----JEFF-311 MATERIAL 9752
-----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: JENDL-3.3 **
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JENDL-3.2 data were automatically transformed to JENDL-3.3.
Interpolation of spectra: 22 (unit base interpolation)
(3,251) deleted, T-matrix of (4,2) deleted, and others.
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HISTORY
85-03 NEW EVALUATION FOR JENDL-3 WAS MADE BY Y.KIKUCHI AND
T.NAKAGAWA (JAERI). DETAILS ARE GIVEN IN REF. /1/.
88-02 DATA WERE CHECKED AND COPIED INTO JENDL-3.
MF=1 GENERAL INFORMATION
MT=451 COMMENTS AND DICTIONARY
MT=452 NUMBER OF NEUTRONS PER FISSION
SUM OF MT'S =455 AND 456.
MT=455 DELAYED NEUTRON DATA
SEMI-EMPIRICAL FORMULA BY TUTTLE /2/.
MT=456 DELAYED NEUTRON DATA
SEMI-EMPIRICAL FORMULA BY HOWERTON /3/.
MF=2,MT=151 RESONANCE PARAMETERS
RESOLVED RESONANCES FOR MLBW FORMULA : 1.0E-5 EV TO 60 EV
RESONANCE ENERGIES, NEUTRON AND RADIATIVE WIDTHS WERE TAKEN
FROM THE EXPERIMENTAL DATA OF BENJAMIN+ /4/. FOR RESONANCES
WHOSE RADIATIVE WIDTH WAS UNKNOWN, THE AVERAGE VALUE OF 0.0357
EV /4/ WAS ADOPTED. FISSION WIDTH OF 0.0002 EV WAS ESTIMATED
FROM THE THERMAL FISSION CROSS SECTION, WHICH WAS ESTIMATED
FROM THE SYSTEMATICS OF CAPTURE TO FISSION RATIO BY PRINCE/5/.
THE PARAMETERS OF THE NEGATIVE RESONANCE WERE ADJUSTED SO AS
TO REPRODUCE THE THERMAL CROSS SECTIONS. NO BACKGROUND
CORRECTION WAS APPLIED.
UNRESOLVED RESONANCES : 60 EV - 30 KEV
OBTAINED FROM OPTICAL MODEL CALCULATION:
S1=3.0E-4 ,S2=0.83E-4 ,R=9.07 FM.
ESTIMATED FROM RESOLVED RESONANCES:
DOBS=1.16 EV, GAM-G=35.7 MILLI-EV ,S0=1.13E-4
GAM-F=0.2 MILLI-EV.
CALCULATED 2200 M/S CROSS SECTIONS AND RESONANCE INTEGRALS
2200 M/S VALUE RES. INT.
TOTAL 717.5 B -
ELASTIC 3.93 B -
FISSION 3.96 B 12.1 B
CAPTURE 709.6 B 1130 B
MF=3 NEUTRON CROSS SECTIONS
MT=1,2,4,51-68,91,102,251 SIG-T,SIG-EL,SIG-IN,SIG-C,MU-BAR
CALCULATED WITH OPTICAL AND STATISTICAL MODELS.
OPTICAL POTENTIAL PARAMETERS WERE OBTAINED BY FITTING THE
TOTAL CROSS SECTION OF PHILLIPS AND HOWE /6/ FOR AM-241:
V = 43.4 - 0.107*EN (MEV)
WS= 6.95 - 0.339*EN + 0.0531*EN**2 (MEV)
WV= 0 , VSO = 7.0 (MEV)
R = RSO = 1.282 , RS = 1.29 (FM)
A = ASO = 0.60 , B = 0.5 (FM)
STATISTICAL MODEL CALCULATION WITH CASTHY CODE /7/.
COMPETING PROCESSES : FISSION,(N,2N),(N,3N),(N,4N).
LEVEL FLUCTUATION CONSIDERED.
THE LEVEL SCHEME TAKEN FROM REF. /8/.
NO. ENERGY(KEV) SPIN-PARITY
G.S. 0 7/2 +
1 8.8 3/2 -
2 39.6 5/2 -
3 41.8 9/2 +
4 82.6 7/2 -
5 93.74 11/2 +
6 137.7 9/2 -
7 155.84 13/2 +
8 204.6 11/2 -
9 229.3 15/2 +
10 283.0 13/2 -
11 313.0 17/2 +
12 372.8 15/2 -
13 377.6 1/2 +
14 389.2 5/2 +
15 410.6 3/2 +
16 421.3 5/2 +
17 428.9 7/2 +
18 474.9 9/2 +
CONTINUUM LEVELS ASSUMED ABOVE 519 KEV.
THE LEVEL DENSITY PARAMETERS : GILBERT AND CAMERON /9/.
GAMMA-RAY STRENGTH FUNCTION OF 3.2E-2 DEDUCED FROM
RESONANCE PARAMETERS.
MT=16,17,37 (N,2N),(N,3N),(N,4N)
CALCULATED WITH EVAPORATION MODEL.
MT=18 FISSION
EVALUATED ON THE BASIS OF THE MEASURED DATA BY
SILBERT/10/, VOROTONIKOV+/11/ AND FOMUSHKIN+ /12/.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2,51-68 CALCULATED WITH OPTICAL MODEL.
MT=16,17,18,37,91 ISOTROPIC IN THE LABORATORY SYSTEM.
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=16,17,37,91 EVAPORATION SPECTRUM.
MT=18 MAXWELLIAN FISSION SPECTRUM.
TEMPERATURE ESTIMATED FROM SYSTEMATICS OF
SMITH+/13/.
REFERENCES
1) KIKUCHI Y. AND NAKAGAWA T.: JAERI-M 85-138 (1985).
2) TUTTLE R.J.: INDC(NDS)-107/G+SPECIAL, P.29 (1979).
3) HOWERTON R.J.: NUCL. SCI. ENG., 62, 438 (1977).
4) BENJAMIN R.W. ET AL.: NUCL. SCI. ENG., 85, 261 (1983).
5) PRINCE A.: TRANS. AM. NUCL. SOC., 10, 228 (1967)
6) PHILLIPS T.W. AND HOWE F.R.: NUCL. SCI. ENG., 69, 375 (1979).
7) IGARASI S.: J. NUCL. SCI. TECHNOL., 12, 67 (1975).
8) LEDERER C.M. AND SHIRLEY V.S.: TABLE OF ISOTOPES , 7TH ED.
9) GILBERT A. AND CAMERON A.G.W.: CAN. J. PHYS., 43, 1446 (1965).
10) SILBERT M.G.: NUCL. SCI. ENG., 63, 198 (1977).
11) VOROTNIKOV I.V. ET AL.: SOV. J. NUCL. PHYS., 10, 419 (1970).
12) FOMSHKIN E.F. ET AL.: SOV. J. NUCL. PHYS., 14, 41(1972).
13) SMITH A.B. ET AL.: ANL/NDM-50 (1979).
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