90-Th-227
90-TH-227 TIT EVAL-AUG88 N.TAKAGI
DIST-SEP89 REV2-JUN94
----JENDL-3.2 MATERIAL 9025
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
88-08 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 ADOPTED
FROM THE EVALUATION 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 1749.40 B -
ELASTIC 12.40 B -
FISSION 202.00 B 210 B
CAPTURE 1535.00 B 1420 B
MF=3 NEUTRON CROSS SECTIONS
MT=1 TOTAL CROSS SECTION
BELOW 0.45 EV, CALCULATED AS SUM OF MT'S = 2, 18 AND 102.
ABOVE 0.45 EV, OPTICAL MODEL CALCULATION WAS MADE WITH
CASTHY/8/. THE POTENTIAL PARAMETERS/9/ USED ARE AS
FOLLOWS,
V = 41.0 - 0.05*EN (MEV)
WS= 6.4 - 0.15*SQRT(EN) (MEV)
WV= 0 , VSO = 7.0 (MEV)
R = RSO = 1.31 , RS = 1.38 (FM)
A = ASO = 0.47 , B = 0.47 (FM)
MT=2 ELASTIC SCATTERING CROSS SECTION
BELOW 0.45 EV, THE CONSTANT CROSS SECTION OF 12.4 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, 91 INELASTIC SCATTERING CROSS SECTIONS.
OPTICAL AND STATISTICAL MODEL CALCULATION WAS MADE WITH
CASTHY/8/. NO EXCITED LEVELS WERE TAKEN INTO THE
CALCULATION.
NO ENERGY(KEV) SPIN-PARITY
G.S. 0.0 3/2 +
LEVELS ABOVE 9.3 KEV/10/ 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
MEASURED THERMAL CROSS SECTION OF 202 BARNS WAS TAKEN FROM
REF./12/, AND 1/V FORM WAS ASSUMED BELOW 0.45 EV. IN THE
ENERGY RANGE ABOVE 0.45 EV, THE SHAPE WAS ASSUMED TO BE
THE SAME AS TH-233 FISSION CROSS SECTION AND IT WAS
NORMALIZED TO THE SYSTEMATICS OF BEHRENS AND HOWERTON/13/.
MT=102 CAPTURE CROSS SECTION
THE THERMAL CROSS SECTION OF 1535 BARNS WAS ESTIMATED FROM
THE RATIO OF FISSION AND CAPTURE CROSS SECTIONS AT 1 EV
AND THE MEASURED FISSION CROSS SECTION AT 0.0253 EV/12/,
AND THE 1/V FORM WAS ASSUMED BELOW 0.45 EV. ABOVE 0.45
EV, CROSS SECTION WAS CALCULATED WITH CASTHY. THE GAMMA-
RAY STRENGTH FUNCTION WAS ESTIMATED FROM GAMMA-GAMMA =
0.040 EV AND LEVEL SPACING = 0.9 EV.
MT=251 MU-L
CALCULATED WITH CASTHY.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2,91 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) OHSAWA T. AND OHTA M.: J. NUCL. SCI. TECHNOL., 18, 408(1981).
10) MAPLES C.: NUCL. DATA SHEETS, 22, 275 (1977).
11) GILBERT A. AND CAMERON A.G.W.: CAN. J. PHYS., 43, 1446(1965).
12) MUGHABGHAB S.F.: "NEUTRON CROSS SECTIONS, VOL.1, NEUTRON
RESONANCE PARAMETERS AND THERMAL CROSS SECTIONS , PART B,
Z=61-100", ACADEMIC PRESS (1984).
13) BEHRENS J.W. AND HOWERTON R.J: NUCL. SCI. ENG., 65, 464(1978).
14) SMITH A.B. ET AL.: ANL/NDM-50 (1979).