95-AM-241 JAERI EVAL-MAR88 T.NAKAGAWA
JAERI-M 89-008 DIST-SEP89
----JENDL-3.2 MATERIAL 9543
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
82-03 EVALUATION FOR JENDL-2 WAS MADE BY Y.KIKUCHI (JAERI) /1/.
88-03 RE-EVALUATION FOR JENDL-3 WAS MADE BY T.NAKAGAWA (JAERI)
/2/.
MF=1 GENERAL INFORMATION
MT=451 COMMENT AND DICTIONARY
MT=452 NUMBER OF NEUTRONS PER FISSION
SUM OF NU-P (MT=456) AND NU-D (MT=455).
MT=455 DELAYED NEUTRON DATA
ESTIMATED WITH SEMI-EMPIRICAL FORMULA BY TUTTLE /3/.
MT=456 NUMBER OF PROMPT NEUTRONS
EXPERIMENTAL DATA OF JAFFEY AND LERNER /4/.
MF=2,MT=151 RESONANCE PARAMETERS
RESOLVED RESONANCES FOR MLBW FORMULA : 1.0E-5 - 150 EV
DATA OF DERRIEN AND LUCAS /5/ WERE ADOPTED AND 5 NEGATIVE
RESONANCES WERE ADDED. VALUES OF TOTAL SPIN J WERE
REPLACED WITH ARBITRARILY ASSUMED VALUES.
UNRESOLVED RESONANCES : 150 EV - 30 KEV
PARAMETERS WERE DETERMINED BY USING ASREP/6/ SO AS TO
REPRODUCE THE CAPTURE CROSS SECTION MEASURED BY VANPRAET
ET AL. /7/ AND THE FISSION CROSS SECTION BY DABBS ET AL.
/8/.
ENERGY INDEPENDENT PARAMETERS:
R=9.37 FM, GAM-G=0.044 EV, DOBS=0.4 EV
ENERGY DEPENDENT PARAMETERS:
AT 150 EV: S0= 1.08E-4, S1=2.72E-4, WF=0.24 MILLI-EV
AT 30 KEV: S0= 0.79E-4, S1=1.99E-4, WF=0.30 MILLI-EV
CALCULATED 2200-M/S CROSS SECTIONS AND RESONANCE INTEGRALS
2200 M/S VALUE RES. INT.
TOTAL 614.6 B -
ELASTIC 11.13 B -
FISSION 3.018 B 13.9 B
CAPTURE 600.4 B 1300 B
MF=3 NEUTRON CROSS SECTIONS
MT=1,2 TOTAL AND ELASTIC SCATTERING CROSS SECTIONS
CALCULATED WITH OPTICAL AND STATISTICAL MODELS BY USING
CASTHY/9/. OPTICAL POTENTIAL PARAMETERS/10/ WERE OBTAINED
BY FITTING THE DATA OF PHILLIPS AND HOWE /11/ :
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=4,51-66,91 INELASTIC SCATTERING CROSS SECTIONS
OPTICAL AND STATISTICAL MODEL CALCULATION WITH CASTHY CODE
/9/. THE LEVEL SCHEME WAS TAKEN FROM REF. /12/
NO ENERGY(KEV) SPIN-PARITY
G.S. 0 5/2 -
1 41.176 7/2 -
2 93.65 9/2 -
3 158.0 11/2 -
4 205.883 5/2 +
5 235.0 7/2 +
6 272.0 9/2 +
7 320.0 11/2 +
8 471.81 3/2 -
9 504.448 5/2 -
10 549.0 7/2 -
11 623.1 1/2 +
12 636.861 3/2 -
13 652.089 1/2 -
14 653.23 3/2 +
15 670.24 3/2 +
16 682.0 11/2 -
CONTINUUM LEVELS ASSUMED ABOVE 732 KEV.
THE LEVEL DENSITY PARAMETERS WERE DETERMINED ON THE BASIS
OF NUMBER OF EXCITED LEVELS/13/ AND RESONANCE LEVEL
SPACING/14/.
AM-242 AM-241
A(1/MEV) 29.6 29.0
T(MEV) 0.342 0.367
C(1/MEV) 22.98 9.95
E-X(MEV) 2.323 3.122
SPIN-CUTOFF(1/MEV**0.5) 30.85 30.45
PAIRING E(MEV) 0.0 0.43
MT=16,17 (N,2N) AND (N,3N) REACTION CROSS SECTIONS
JENDL-2 DATA CALCULATED WITH EVAPORATION MODEL WERE
ADOPTED.
MT=18 FISSION CROSS SECTION
EVALUATED ON THE BASIS OF THE DATA BY DABBS ET AL./8/
MT=102 CAPTURE CROSS SECTION
EVALUATED ON THE BASIS OF THE MEASURED DATA OF VANPRAET ET
AL./7/ IN THE UNRESOLVED RESONANCE REGION. ABOVE 30 KEV,
CALCULATION WITH CASTHY WAS ADOPTED. THE GAMMA-RAY
STRENGTH FUNCTION WAS DETERMINED SO THAT THE CROSS SECTION
WAS 1.7 BARNS AT 60 KEV.
MT=251 MU-BAR
CALCULATED WITH OPTICAL MODEL.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2,51-66,91 CALCULATED WITH CASTHY.
MT=16,17,18 ISOTROPIC IN THE LAB SYSTEM.
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=16,17,91 EVAPORATION SPECTRUM.
MT=18 MAXWELLIAN FISSION SPECTRUM. TEMPERATURE
WAS ESTIMATED FROM Z**2/A VALUES /15/.
REFERENCES
1) KIKUCHI Y.: JAERI-M 82-096 (1982).
2) NAKAGAWA T.: JAERI-M 88-008 (1989).
3) TUTTLE R.J.: INDC(NDS)-107/G+SPECIAL, P.29 (1979).
4) JAFFEY A.H. AND LERNER J.L.: NUCL.PHYS.,A145,1 (1970).
5) DERRIEN H. AND LUCAS B.: 1975 WASHINGTON, P.637,
NBS-SP-425 (1975).
6) KIKUCHI Y.: PRIVATE COMMUNICATION.
7) VANPRAET G. ET AL.: 1985 SANTA FE, 1, 493 (1986).
8) DABBS J.W.T. ET AL.: NUCL. SCI. ENG., 83, 22 (1983).
9) IGARASI S.: J.NUCL.SCI.TECHNOL.,12,67 (1975).
10) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).
11) PHILLIPS T.W. AND HOWE R.E.: NUCL. SCI. ENG., 69, 375 (1979).
12) ELLIS-AKOVALI Y.A.: NUCL. DATA SHEETS, 44, 407 (1985).
13) ENSDF, EVALUATED NUCLEAR STRUCTURE DATA FILE (1988).
14) MUGHABGHAB S.F.: "NEUTRON CROSS SECTIONS, VOL. 1, PART B",
ACADEMIC PRESS, INC. (1984).
15) SMITH A.B. ET AL.: ANL/NDM-50 (1979).