99-Es-254
99-ES-254 TIT EVAL-AUG87 N.TAKAGI
DIST-SEP89 REV2-JUN94
----JENDL-3.2 MATERIAL 9914
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
87-08 NEW EVALUATION WAS MADE BY N. TAKAGI (TOKYO INSTITUTE OF
TECHNOLOGY, TIT) /1/.
94-06 JENDL-3.2.
NU-P, NU-D AND NU-TOTAL WERE MODIFIED.
COMPILED BY T.NAKAGAWA (NDC/JAERI)
***** MODIFIED PARTS FOR JENDL-3.2 ********************
(1,452), (1,455), (1,456)
***********************************************************
MF=1 GENERAL INFORMATION
MT=451 COMMENT AND DICTIONARY
MT=452 NUMBER OF NEUTRONS PER FISSION
SUM OF NU-P NAD NU-D.
MT=455 DELAYED NEUTRONS PER FISSION
AVERAGE VALUES OF SYSTEMATICS BY TUTTLE/2/, BENEDETTI ET
AL./3/ AND WALDO ET AL./4/ DECAY CONSTANTS WERE EVALUATED
BY BRADY AND ENGLAND/5/.
MT=456 PROMPT NEUTRONS PER FISSION
CALCULATED FROM THE SEMI-EMPIRICAL FORMULA OF HOWERTON/6/.
MF=2 RESONANCE PARAMETERS
MT=151 RESONANCE PARAMETERS
NO RESONANCE PARAMETERS WERE GIVEN.
2200-M/S CROSS SECTIONS AND RESONANCE INTEGRALS
2200 M/S VALUE RES. INT.
TOTAL 2004.90 B -
ELASTIC 10.60 B -
FISSION 1966.00 B 1220 B
CAPTURE 28.30 B 18.0 B
MF=3 NEUTRON CROSS SECTIONS
MT=1 TOTAL CROSS SECTION
BELOW 5 EV, CALCULATED AS SUM OF MT'S = 2, 18 AND 102.
ABOVE 5 EV, OPTICAL MODEL CALCULATION WAS MADE WITH
CASTHY/7/. THE POTENTIAL PARAMETERS/8/ USED ARE AS
FOLLOWS,
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)
MT=2 ELASTIC SCATTERING CROSS SECTION
BELOW 5 EV, THE CONSTANT CROSS SECTION OF 10.6 BARNS WAS
ASSUMED, WHICH WAS THE SHAPE ELASTIC SCATTERING CROSS
SECTION CALCULATED WITH OPTICAL MODEL. ABOVE THIS ENERGY,
OPTICAL MODEL CALCULATION WAS ADOPTED.
MT=4,51-52,91 INELASTIC SCATTERING CROSS SECTIONS.
OPTICAL AND STATISTICAL MODEL CALCULATION WAS MADE WITH
CASTHY/7/. THE LEVEL SCHEME WAS TAKEN FROM REF./9/.
NO ENERGY(KEV) SPIN-PARITY
G.S. 0.0 7 +
1 78.0 2 +
LEVELS ABOVE 503 KEV WERE ASSUMED TO BE OVERLAPPING.
THE LEVEL DENSITY PARAMETERS WERE TAKEN FROM REF./10/.
MT=16,17,37 (N,2N), (N,3N) AND (N,4N) REACTION CROSS SECTIONS
CALCULATED WITH EVAPORATION MODEL.
MT=18 FISSION CROSS SECTION
MEASURED THERMAL CROSS SECTION OF 1966 BARNS WAS TAKEN
FROM REF./11/. THE 1/V FORM WAS ASSUMED BELOW 5 EV. THE
SHAPE OF CROSS SECTION NEAR 5 EV WAS ADJUSTED SO AS TO
REPRODUCE THE MEASURED RESONANCE INTEGRAL OF 1200+-250
BARNS/11/. ABOVE 5 EV, THE CROSS SECTION SHAPE WAS
ASSUMED TO BE THE SAME AS BK-250 FISSION CROSS SECTION
AND IT WAS NORMALIZED TO SYSTEMATICS OF BEHRENS AND
HOWERTON/12/.
MT=102 CAPTURE CROSS SECTION
MEASURED THERMAL CROSS SECTION OF 28.3 BARNS WAS TAKEN
FROM REF./11/, AND 1/V FORM WAS ASSUMED BELOW 5 EV. THE
CROSS SECTION NEAR 5 EV WAS ADJUSTED SO AS TO REPRODUCE
THE MEASURED RESONANCE INTEGRAL OF 18.2+-1.5 BARNS/11/.
ABOVE 5 EV, CALCULATED WITH CASTHY. THE GAMMA-RAY STRENGTH
FUNCTION WAS ESTIMATED FROM GAMMA-GAMMA = 0.040 EV AND
LEVEL SPACING = 2 EV.
MT=251 MU-L
CALCULATED WITH CASTHY.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2,51-52,91 CALCULATED WITH OPTICAL MODEL.
MT=16,17,18,37 ISOTROPIC IN THE LAB SYSTEM.
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=16,17,37,91 EVAPORATION SPECTRA
OBTAINED FROM LEVEL DENSITY PARAMETERS.
MT=18 MAXWELLIAN FISSION SPECTRUM.
TEMPERATURE WAS ESTIMATED FROM Z**2/A DEPENDENCE/13/.
REFERENCES
1) TAKAGI N. ET AL.: J. NUCL. SCI. TECHNOL., 27, 853 (1990).
2) TUTTLE R.J.: INDC(NDS)-107/G+SPECIAL, P.29 (1979),
3) BENEDETTI G. ET AL.: NUCL. SCI. ENG., 80, 379 (1982).
4) WALDO R. ET AL.: PHYS. REV., C23, 1113 (1981).
5) BRADY M.C. AND ENGLAND T.R.: NUCL. SCI. ENG., 103, 129 (1989).
6) HOWERTON R.J.: NUCL. SCI. ENG., 62, 438 (1977).
7) IGARASI S. AND FUKAHORI T.: JAERI 1321(1991).
8) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).
9) SCHMORAK M.R.: NUCL. DATA SHEETS, 32, 87 (1981).
10) GILBERT A. AND CAMERON A.G.W.: CAN. J. PHYS., 43, 1446 (1965).
11) MUGHABGHAB S.F.: "NEUTRON CROSS SECTIONS, VOL.1, NEUTRON
RESONANCE PARAMETERS AND THERMAL CROSS SECTIONS , PART B,
Z=61-100", ACADEMIC PRESS (1984).
12) BEHRENS J.W. AND HOWERTON R.J: NUCL. SCI. ENG., 65, 464
(1978).
13) SMITH A.B. ET AL.: ANL/NDM-50 (1979).