96-Cm-245
96-CM-245 JAERI EVAL-MAR89 T.NAKAGAWA
DIST-MAR89 REV2-SEP92
----JENDL-3.2 MATERIAL 9640
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
78-03 EVALUATION WAS MADE BY S.IGARASI AND T.NAKAGAWA (JAERI)/1/.
89-03 RE-EVALUATION FOR JENDL-3 WAS MADE BY T.NAKAGAWA(JAERI)/2/.
90-07 SPIN IN MF2,MT151 WAS CORRECTED.
92-09 JENDL-3.2.
COMPILED BY T.NAKAGAWA (NDC/JAERI)
***** MODIFIED PARTS FOR JENDL-3.2 ********************
(1,452), (1,456)
***********************************************************
MF=1 GENERAL INFORMATION
MT=451 DESCRIPTIVE DATA
MT=452 NUMBER OF NEUTRONS PER FISSION
SUM OF MT=455 AND MT=456.
MT=455 NUMBER OF DELAYED NEUTRONS PER FISSION
ESTIMATED FROM THE SYSTEMATICS PROPOSED BY TUTTLE /3/.
MT=456 NUMBER OF PROMPT NEUTRONS PER FISSION
EXPERIMENTAL RESULTS OF KHOKHLOV ET AL./4/ WERE ADOPTED.
MF=2 RESONANCE PARAMETERS
MT=151 RESONANCE PARAMETERS
RESOLVED RESONANCE REGION (SLBW) : 1.0E-5 TO 60 EV
PARAMETERS FOR REICH-MOORE FORMULA BY MOORE AND KEYWORTH
/5/ WERE ADOPTED ABOVE 20 EV, AND THOSE BY BROWNE ET AL.
/6/ BELOW 20 EV WITH A LITTLE MODIFICATION OF A NEGATIVE
RESONANCE SO THAT THE THERMAL CROSS SECTION COULD BE IN
AGREEMENT WITH THE EXPERIMENTAL DATA. THE DIFFERENCES
BETWEEN REICH-MOORE AND SINGLE-LEVEL B-W FORMULAS ARE
TREATED AS THE BACKGROUND CROSS SECTIONS.
RADIATIVE WIDTH = 0.04 EV
SCATTERING RADIUS = 10.0 FM
UNRESOLVED RESONANCE PARAMETERS : 60 EV - 40 KEV
PARAMETERS WERE DETERMINED WITH A FITTING CODE ASREP/7/
SO AS TO REPRODUCE THE FISSION CROSS SECTION OF MOORE AND
KEYWORTH /5/, AND THE TOTAL AND CAPTURE CROSS SECTIONS
CALCULATED WITH OPTICAL AND STATISTICAL MODELS.
ENERGY INDEPENDENT PARAMETERS:
R=9.43 FM, S0=1.02E-4, S1=2.24E-4, S2=0.9E-4,
WG=0.04 EV.
ENERGY DEPENDENT PARAMETERS AT 1 KEV:
WF=2.01 EV, D=1.397 EV.
CALCULATED 2200M/S CROSS SECTIONS AND RESONANCE INTEGRALS.
2200 M/SEC RES. INTEG.
TOTAL 2359. B -
ELASTIC 11.59 B -
FISSION 2001. B 801 B
CAPTURE 346.4 B 110 B
MF=3 NEUTRON CROSS SECTIONS
BELOW 40 KEV, CROSS SECTIONS WERE REPRESENTED WITH RESONANCE
PARAMETERS.
MT=1,2,4,51-73,91,102,251 TOTAL, ELASTIC AND INELASTIC
SCATTERING, CAPTURE CROSS SECTIONS AND MU-L
CALCULATED WITH OPTICAL AND STATISTICAL MODEL CODE
CASTHY/8/.
THE SPHERICAL OPTICAL POTENTIAL PARAMETERS (MEV,FM):
V =42.7-0.107*EN, R =1.282, A =0.60
WS =6.95-0.339*EN+0.0531*EN**2, RS =1.29, B =0.50
(DERIVATIVE WOODS-SAXON FORM)
VSO=7.0, RSO=1.282, ASO=0.60
THIS SET OF POTENTIAL PARAMETERS WAS DETERMINED /9/ TO
REPRODUCE WELL THE TOTAL CROSS SECTION OF AM-241 BY
PHILLIPS AND HOWE /10/. THE STRENGTH FUNCTION OF 1.02E-4
CALCULATED WITH THIS OMP IS IN GOOD AGREEMENT WITH
1.18E-4/11/.
IN THE STATISTICAL MODEL CALCULATION, COMPETING PROCESSES
OF FISSION, (N,2N), (N,3N) AND (N,4N), AND LEVEL
FLUCTUATION WERE CONSIDERED. THE LEVEL SCHEME OF CM-245
WAS TAKEN FROM THE COMPILATION BY ELLIS-AKOVALI /12/:
NO. ENERGY(MEV) SPIN-PARITY
G.S. 0.0 7/2 +
1 0.0548 9/2 +
2 0.1215 11/2 +
3 0.1974 13/2 +
4 0.25285 5/2 +
5 0.2958 7/2 +
6 0.35086 9/2 +
7 0.35595 1/2 +
8 0.3615 3/2 +
9 0.3883 9/2 -
10 0.4167 11/2 +
11 0.4188 5/2 +
12 0.431 5/2 +
13 0.4429 11/2 -
14 0.498 13/2 +
15 0.5091 13/2 -
16 0.532 9/2 +
17 0.555 11/2 +
18 0.63365 3/2 -
19 0.6435 7/2 -
20 0.66155 5/2 -
21 0.7018 9/2 -
22 0.722 7/2 +
23 0.741 1/2 +
OVERLAPPING LEVELS ARE ASSUMED ABOVE 0.82 MEV. LEVELS
WITH HIGHER SPIN THAN 13/2 OR WHOSE SPIN WAS UNKNOWN WERE
NEGLECTED. THE LEVEL DENSITY PARAMETERS WERE DETERMINED
ON THE BASIS OF NUMBERS OF EXCITED LEVELS/13/ AND
RESONANCE LEVEL SPACING/11/.
CM-246 CM-245
A(1/MEV) 27.7 30.0
T(MEV) 0.395 0.391
C(1/MEV) 2.2560 11.288
E-X(MEV) 4.1307 4.0295
SPIN-CUTOFF(1/MEV**0.5) 30.17 31.31
PAIRING E(MEV) 1.11 0.72
AVERAGE RADIATIVE WIDTH = 0.040 EV AND D = 1.4 EV /11/
WERE USED FOR THE CAPTURE CROSS SECTION CALCULATION.
MT=16,17,37 (N,2N). (N,3N) AND (N,4N) CROSS SECTIONS
CALCULATED WITH THE EVAPORATION MODEL BY PEARLSTEIN /14/.
NEUTRON EMISSION CROSS SECTION WAS ASSUMED TO BE (COMPOUND
NUCLEUS FORMATION CROSS SECTION CALCULATED WITH OPTICAL
MODEL - FISSION).
MT=18 FISSION CROSS SECTION
BELOW 100 KEV: JENDL-2 WAS ADOPTED, WHICH WAS OBTAINED BY
FITTING A SEMI-EMPIRICAL FORMULA TO THE
EXPERIMENTAL DATA OF REF./5/.
ABOVE 100 KEV: BASED ON THE EXPERIMENTAL DATA OF WHITE
AND BROWNE /15/.
MF=4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
MT=2,51-73,91
LEGENDRE COEFFICIENTS WERE GIVEN BY THE OPTICAL AND
STATISTICAL MODEL CALCULATIONS.
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
MT=18 FISSION SPECTRUM ESTIMATED FROM Z**2/A SYSTEMATICS BY
SMITH ET AL./16/ BY ASSUMING E(CF-252) = 2.13 MEV.
REFERENCES
1) IGARASI S. AND NAKAGAWA T.: JAERI-M 7733 (1978).
2) NAKAGAWA T.: JAERI-M 90-101 (1990).
3) TUTTLE R.J.: PROC. CONSULTANTS' MEETING ON DELAYED NEUTRON
PROPERTIES, 1973 VIENNA, 29, ALSO INDC(NDS)-107/G+SPECIAL
(1979).
4) KHOKHLOV YU.A. ET AL.: INT. SEMINAR ON INTERACTION OF NEUTRONS
WITH NUCLEI, 1992 DUBUNA, NO.5.5 (1992).
5) MOORE M.S. AND KEYWORTH G.A.: PHYS. REV., C3, 1656 (1971).
6) BROWNE J.C. ET AL. : NUCL. SCI. ENG., 65, 166 (1978).
7) KIKUCHI Y.: PRIVATE COMMUNICATION.
8) IGARASI S. AND FUKAHORI T.: JAERI 1321 (1991).
9) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).
10) PHILLIPS T.W. AND HOWE R.E.: NUCL. SCI. ENG. 69, 375 (1979).
11) MUGHABGHAB S.F.: "NEUTRON CROSS SECTIONS, VOL.1, PART B",
ACADEMIC PRESS (1984).
12) ELLIS-AKOVALI Y.A.: NUCL. DATA SHEETS, 33, 119 (1981).
13) ENSDF, EVALUATED NUCLEAR STRUCTURE DATA FILE, AS OF JAN. 1989.
14) PEARLSTEIN S.: NUCL. SCI. ENG., 23, 238 (1965).
15) WHITE R.M. AND BROWNE J.C.: 1983 ANTWERP, 218 (1983).
16) SMITH A.B. ET AL.: ANL/NDM-50 (1979).