95-AM-242 JAERI EVAL-MAR80 T.NAKAGAWA, S.IGARASI
JAERI-M 8903 (1980) DIST-SEP89
----JENDL-3.2 MATERIAL 9546
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
80-03 NEW EVALUATION WAS MADE BY T.NAKAGAWA AND S.IGARASI(JAERI).
DETAILS ARE GIVEN IN REF. /1/.
87-04 FORMAT WAS TRANSLATED TO ENDF-5 FORMAT.
88-03 SINCE NO RECENT EXPERIMENTAL DATA WERE AVAILABLE, THE DATA
OF JENDL-2 WERE ADOPTED FOR JENDL-3.
MF=1 GENERAL INFORMATION
MT=451 COMMENT AND DICTIONARY
MT=452 NUMBER OF NEUTRONS PER FISSION
SUM OF PROMPT AND DELAYED NEUTRONS.
MT=455 DELAYED NEUTRON DATA
ESTIMATED FROM TUTTLE'S SEMI-EMPIRICAL FORMULA /2/.
MT=456 NUMBER OF PROMPT NEUTRONS PER FISSION
SEMI-EMPIRICAL FORMULA BY HOWERTON /3/
NU-P= 3.268 + 0.172*E(MEV).
MF=2 RESONANCE PARAMETERS
MT=151 NO RESONANCE PARAMETERS
2200M/S CROSS SECTIONS AND CALCULATED RESONANCE INTEGRALS.
2200 M/SEC RES. INTEG.
TOTAL 7611.44 B -
ELASTIC 11.44 B -
FISSION 2100.0 B 1260 B
CAPTURE 5500.0 B 391 B
MF=3 NEUTRON CROSS SECTIONS
MT=1,2,4,51-72,91,102,251 SIG-T,SIG-EL,SIG-IN,SIG-C,MU-BAR
BELOW 0.225 EV:
1/V FORM WAS ASSUMED FOR FISSION AND CAPTURE CROSS
SECTIONS. EFFECTIVE SCATTERING RADIUS OF 9.54 FM WAS
USED FOR ELASTIC SCATTERING CROSS-SECTION CALCULATION.
ABOVE 0.225 EV:
OPTICAL AND STATISTICAL MODELS WERE USED.
THE SPHERICAL OPTICAL POTENTIAL PARAMETERS (MEV, FM) :
V= 42.0 - 0.107*E , R= 1.282 , A= 0.6
WS= 9.0 - 0.339*E + 0.0531*E**2 , R= 1.29 , A= 0.5
VSO= 7.0 , R= 1.282 , A= 0.6
STATISTICAL MODEL CALCULATION WITH CASTHY CODE /4/.
COMPETING PROCESSES : FISSION,(N,2N) AND (N,3N).
LEVEL FLUCTUATION CONSIDERED. GAM-G = 0.05 EV AND
D = 0.45 EV USED FOR CAPTURE CROSS SECTION CALCULATION
THE LEVEL SCHEME TAKEN FROM THE COMPILATION BY ELLIS
AND HAESE /5/.
NO. ENERGY(MEV) SPIN-PARITY
G.S. 0.0 1 -
1 0.044 0 -
2 0.049 3 -
3 0.049 5 -
4 0.074 2 -
5 0.113 6 -
6 0.148 4 -
7 0.148 5 -
8 0.190 7 -
9 0.242 3 -
10 0.263 6 -
11 0.263 7 -
12 0.288 4 -
13 0.288 2 -
14 0.325 3 -
15 0.341 5 -
16 0.372 4 -
17 0.410 6 -
18 0.430 5 -
19 0.488 7 -
20 0.500 6 -
21 0.581 7 -
22 0.679 8 -
OVERLAPPING LEVELS ARE ASSUMED ABOVE 0.681 MEV.
THE LEVEL DENSITY PARAMETERS OF GILBERT AND CAMERON /6/.
MT=16,17 (N,2N) AND (N,3N) CROSS SECTIONS
CALCULATED WITH THE EVAPORATION MODEL BY PEARLSTEIN /7/.
MT=18 FISSION CROSS SECTION
THE EMPIRICAL FORMULA USED FOR THE AM-242M DATA WAS
APPLIED BY SHIFTING THE ENERGY ORIGIN TO -49 KEV.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2 LEGENDRE COEFFICIENTS ARE GIVEN BY THE OPTICAL AND
STATISTICAL MODEL CALCULATIONS.
MT=16,17,18,91 ISOTROPIC DISTRIBUTIONS IN THE CENTER-OF-MASS
SYSTEM.
MT=51-72 ISOTROPIC DISTRIBUTIONS IN THE LABORATORY SYSTEM.
MF=5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=16,17,91 EVAPORATION SPECTRUM
MT=18 FISSION SPECTRUM ESTIMATED FROM Z**2/A SYSTEMATICS BY
SMITH ET AL. /8/ BY ASSUMING E(CF-252) = 2.13 MEV.
REFERENCES
1) T. NAKAGAWA AND S. IGARASI : JAERI-M 8903 (1980), IN JAPANESE.
2) R.J. TUTTLE : INDC(NDS)-107/G+SPECIAL, 29 (1979).
3) R.J. HOWERTON : NUCL. SCI. ENG., 62, 438 (1977).
4) S. IGARASI : J. NUCL. SCI. TECHNOL., 12, 67(1975).
5) Y.A. ELLIS AND R.L. HAESE : NUCL. DATA SHEETS 21, 615 (1977).
6) A. GILBERT AND A.G.W. CAMERON : CAN. J. PHYS., 43, 1446
(1965).
7) S. PEARLSTEIN : NUCL. SCI. ENG., 23, 238 (1965).
8) A.B. SMITH ET AL. : ANL/NDM-50 (1979).