96-Cm-250
96-CM-250 TIT EVAL-AUG87 N.TAKAGI
DIST-SEP89 REV2-JUN94
----JENDL-3.2 MATERIAL 9655
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
87-08 NEW EVALUATION WAS MADE BY N. TAKAGI (TOKYO INSTITUTE OF
TECHNOLOGY, TIT) /1/.
89-08 CROSS SECTIONS WERE MODIFIED BELOW 90 EV.
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 ASSUMED
TO BE THE SAME AS THOSE OF CM-245 EVALUATED BY BRADY AND
ENGLAND/5/.
MT=456 PROMPT NEUTRONS PER FISSION
BASED ON SYSTEMATICS BY MANERO AND KONSHIN/6/, AND BY
HOWERTON/7/.
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 11.20 B -
ELASTIC 10.80 B -
FISSION 0.002 B 6.86 B
CAPTURE 0.40 B 8.23 B
MF=3 NEUTRON CROSS SECTIONS
MT=1 TOTAL CROSS SECTION
BELOW 90 EV, CALCULATED AS SUM OF MT'S = 2, 18 AND 102.
ABOVE 90 EV, OPTICAL MODEL CALCULATION WAS MADE WITH
CASTHY/8/. THE POTENTIAL PARAMETERS/9/ 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 90 EV, THE CONSTANT CROSS SECTION OF 10.8 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/8/. THE LEVEL SCHEME WAS TAKEN FROM REF./10/.
NO ENERGY(KEV) SPIN-PARITY
G.S. 0 0 +
1 43 2 +
2 142 4 +
LEVELS ABOVE 200 KEV WERE ASSUMED TO BE OVERLAPPING.
THE LEVEL DENSITY PARAMETERS WERE TAKEN FROM REF./11/.
MT=16,17,37 (N,2N), (N,3N) AND (N,4N) REACTION CROSS SECTIONS
CALCULATED WITH EVAPORATION MODEL.
MT=18 FISSION CROSS SECTION
THE CROSS SECTION WAS ASSUMED TO BE 0.1 BARN AT 0.0253 EV
FROM THE SYSTEMATICS OF PRINCE/12/, AND ASSUMED THE FORM
OF 1/V BELOW 90 EV. AT ENERGIES ABOVE 90 EV, THE SHAPE OF
THE CM-248 FISSION CROSS SECTION WAS ADOPTED, AND IT WAS
NORMALIZED TO THE SYSTEMATICS OF BEHRENS AND HOWERTON/13/.
MT=102 CAPTURE CROSS SECTION
THE CROSS SECTION WAS ASSUMED TO BE 20 BARNS AT 0.0253 EV
FROM THE SYSTEMATICS OF PRINCE/12/ AND THE CORRELATION OF
THERMAL CROSS SECTIONS WITH NUMBER OF EXCESS NEUTRON. THE
1/V FORM WAS ASSUMED BELOW 90 EV. ABOVE 90 EV, THE CROSS
SECTION WAS CALCULATED WITH CASTHY. THE GAMMA-RAY STRENGTH
FUNCTION WAS ESTIMATED FROM GAMMA-GAMMA = 0.040 EV AND
LEVEL SPACING = 180 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/14/.
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) MANERO F. AND KONSHIN V.A.: AT. ENERGY REV.,10, 637 (1972).
7) HOWERTON R.J.: NUCL. SCI. ENG., 62, 438 (1977).
8) IGARASI S. AND FUKAHORI T.: JAERI 1321 (1991),
9) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).
10) SCHMORAK M.R.: NUCL. DATA SHEETS, 32, 87 (1981).
11) GILBERT A. AND CAMERON A.G.W.: CAN. J. PHYS., 43, 1446 (1965).
12) PRINCE A.: PROC. CONF. ON NUCL. CROSS SECTIONS AND TECHNOL.,
WASHINGTON D.C., 4-7 MARCH, (1968), NBS SPECIAL PUBLICATION
299, 2, 951 (1968)
13) BEHRENS J.W. AND HOWERTON R.J: NUCL. SCI. ENG., 65, 464(1978).
14) SMITH A.B. ET AL.: ANL/NDM-50 (1979).