95-AM-243 JAERI EVAL-MAR88 T.NAKAGAWA
JAERI-M 89-008 DIST-SEP89
----JENDL-3.2 MATERIAL 9549
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
77-03 NEW EVALUATION WAS MADE BY S.IGARASI AND T.NAKAGAWA (JAERI).
DETAILS ARE GIVEN IN REF. /1/.
82-03 COMPLETE REEVALUATION FOR JENDL-2 WAS MADE BY Y.KIKUCHI
(JAERI). DETAILS ARE GIVEN IN REF. /2/.
88-03 REEVALUATED FOR JENDL-3 WAS MADE BY T.NAKAGAWA (JAERI)/3/.
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 /4/.
MT=456 NUMBER OF PROMPT NEUTRONS
ESTIMATED FROM SYSTEMATICS. SAME AS PREVIOUS EVALUA-
TION /1/.
MF=2,MT=151 RESONANCE PARAMETERS
RESOLVED RESONANCES FOR MLBW FORMULA : 1.0E-5 - 215 EV.
JENDL-2 EVALUATION/2/ WAS BASED ON THE DATA OF SIMPSON ET
AL./5/. THE FISSION WIDTHS WERE MODIFIED FOR JENDL-3 ON
THE BASIS OF KNITTER AND BUDTZ-JORGENSEN/6/. VALUES OF
TOTAL SPIN WERE ASSUMED ARBITRARILY.
UNRESOLVED RESONANCES : 215 EV - 30 KEV
PARAMETERS OF JENDL-2 WERE ADOPTED.
OBTAINED FROM OPTICAL MODEL CALCULATION:
S0=0.93E-4, S1=2.44E-4, R=9.34 FM
ESTIMATED FROM RESOLVED RESONANCES:
DOBS=0.67 EV, WG=0.039 EV, WF=0.00012 EV
CALCULATED 2200-M/S CROSS SECTIONS AND RESONANCE INTEGRALS
2200 M/S VALUE RES. INT.
TOTAL 86.10 B -
ELASTIC 7.483 B -
FISSION 0.1161 B 7.59 B
CAPTURE 78.50 B 1830 B
MF=3 NEUTRON CROSS SECTIONS
BELOW 30 KEV: CROSS SECTIONS WERE REPRESENTED WITH THE
RESONANCE PARAMETERS.
ABOVE 30 KEV:
MT=1,2 TOTAL AND ELASTIC SCATTERING CROSS SECTIONS
CALCULATED WITH OPTICAL AND STATISTICAL MODEL CODE
CASTHY/7/. OPTICAL POTENTIAL PARAMETERS WERE OBTAINED /8/
BY FITTING THE DATA OF PHILLIPS AND HOWE /9/ FOR AM-241:
V = 43.4 - 0.107*EN (MEV)
WS= 6.95 - 0.339*EN + 0.0531*EN**2 (MEV)
VSO = 7.0 (MEV)
R = RSO = 1.282 , RS = 1.29 (FM)
A = ASO = 0.60 , B = 0.5 (FM)
MT=4,51-59,91 INELASTIC SCATTERING CROSS SECTIONS
CALCULATED WITH CASTHY/8/. THE LEVEL SCHEME WAS TAKEN
FROM REF. /10/
NO ENERGY(KEV) SPIN-PARITY
G.S. 0 5/2 -
1 42.2 7/2 -
2 84.0 5/2 +
3 96.4 9/2 -
4 109.3 7/2 +
5 143.5 9/2 +
6 189.3 11/2 +
7 266.0 3/2 -
8 300.0 5/2 -
9 345.0 7/2 -
CONTINUUM LEVELS ASSUMED ABOVE 383 KEV.
THE LEVEL DENSITY PARAMETERS WERE DETERMINED ON THE BASIS
OF NUMBER OF EXCITED LEVELS/11/ AND RESONANCE LEVEL
SPACING/12/.
AM-244 AM-243
A(1/MEV) 30.3 31.3
T(MEV) 0.340 0.355
C(1/MEV) 26.47 11.71
E-X(MEV) 2.373 3.278
SPIN-CUTOFF(1/MEV**0.5) 31.39 31.81
PAIRING E(MEV) 0.0 0.5
MT=16,17,37 (N,2N), (N,3N) AND (N,4N) REACTION CROSS SECTIONS
TAKEN FROM JENDL-2 CALCULATED WITH THE EVAPORATION MODEL.
MT=18 FISSION CROSS SECTION
30 KEV - 100 KEV : SMOOTH CORVE CONNECTING THE DATA IN
THE UNRESOLVED RESONANCE REGION AND ABOVE 100 KEV
100 KEV - 10 MEV : SPLINE-FITTING TO KANDA ET AL./13/,
FURSOV ET AL./14/ AND KNITTER AND BUDTZ-JORGENSEN/6/.
10 MEV - 20 MEV : SHAPE WAS ESTIMATED ON THE BASIS OF
BEHRENS AND BROWNE/15/
MT=102 CAPTURE CROSS SECTION
CALCULATED WITH CASTHY/8/. THE GAMMA-RAY STRENGTH
FUNCTION WAS DETERMINED TO REPRODUCE THE CROSS SECTION
OF 2.2 B AT 30 KEV/16/.
MT=251 MU-L BAR
CALCULATED WITH CASTHY/8/.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2,51-59,91
LEGENDRE COEFFICIENTS WERE GIVEN BY THE OPTICAL AND
STATISTICAL MODEL CALCULATION.
MT=16,17,18,37
ISOTROPIC DISTRIBUTIONS IN THE LABORATORY SYSTEM.
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=16,17,37,91
EVAPORATION SPECTRUM WITH NUCLEAR TEMPERATURE CALCULATED
FROM LEVEL DENSITIES.
MT=18
MAXWELLIAN FISSION SPECTRUM ESTIMATED FROM Z**2/A
SYSTEMATICS BY SMITH ET AL./17/.
REFERENCES
1) IGARASI S. AND NAKAGAWA T.: JAERI-M 7174 (1977).
2) KIKUCHI Y.: JAERI-M 82-096 (1982).
3) NAKAGAWA T.: JAERI-M 89-008 (1989).
4) TUTTLE R.J. : INDC(NDS)-107/G+SPECIAL , P.29 (1979).
5) SIMPSON O.D. ET AL. : NUCL.SCI.ENG.,55,273(1974)
6) KNITTER H.-H AND BUDTZ-JORGENSEN C.: 85 SANTA FE, 1, 413
(1986).
7) IGARASI S. AND FUKAHORI T.: JAERI 1321 (1991).
8) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).
9) PHILLIPS T.W. AND HOWE R.E. : NUCL. SCI. ENG., 69, 375 (1979).
10) ELLIS-AKOVALI Y.A.: NUCL. DATA SHEETS, 33, 79 (1981).
11) ENSDF, EVALUATED NUCLEAR STRUCTURE DATA FILE (1988).
12) MUGHABGHAB S.F.: "NEUTRON CROSS SECTIONS, VOL. 1, PART B",
ACADEMIC PRESS, INC. (1984).
13) KANDA K. ET AL.: J. NUCL. SCI. TECHNOL., 24, 423 (1987).
14) FURSOV B. ET AL.: 85 SANTA FE, 1, 641 (1986).
15) BEHRENS J.W. AND BROWNE J.C.: NUCL. SCI. ENG., 77, 444 (1981).
16) WESTON L.W. AND TODD J.H.: NUCL. SCI. ENG., 91, 444 (1985).
17) SMITH A.B.: ANL/NDM-50 (1979).