55-Cs-135
55-CS-135 JNDC EVAL-MAR90 JNDC FP NUCLEAR DATA W.G.
DIST-NOV90
----JENDL-3.2 MATERIAL 5531
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
HISTORY
84-10 EVALUATION FOR JENDL-2 WAS MADE BY JNDC FPND W.G./1/
90-03 MODIFICATION FOR JENDL-3 WAS MADE/2/.
MF = 1 GENERAL INFORMATION
MT=451 COMMENTS AND DICTIONARY
MF = 2 RESONANCE PARAMETERS
MT=151 RESOLVED AND UNRESOLVED RESONANCE PARAMETERS
RESOLVED RESONANCE REGION (MLBW FORMULA) : BELOW 0.088 KEV
RESONANCE PARAMETERS OF JENDL-2 WERE MODIFIED AS FOLLOWS :
EVALUATION FOR JENDL-2 WAS PERFORMED ON THE BASIS OF THE DATA
(ONLY ONE POSITIVE LEVEL) MEASURED BY PRIESMEYER ET AL./3/
A NEGATIVE RESONANCE WAS ADDED AT -50 EV. THE PARAMETERS WERE
ADJUSTED SO AS TO REPRODUCE THE CAPTURE CROSS SECTION OF
8.7+-0.5 BARNS AT 0.0253 EV AND THE NEUTRON RESONANCE CAPTURE
INTEGRAL OF 62+-2 BARNS GIVEN BY MUGHABGHAB ET AL./4/ SINCE
THE VALUES OF TOTAL SPIN J FOR THE NEGATIVE AND POSITIVE FIRST
LEVELS WERE UNKNOWN, THE TARGET SPIN OF 3.5 WAS ADOPTED AS THE
TOTAL SPIN.
FOR JENDL-3, THE J-VALUES OF THE BOTH LEVELS WERE TENTATIVELY
ESTIMATED WITH A RANDOM NUMBER METHOD. NEUTRON WIDTHS FOR THE
BOTH LEVELS WERE MODIFIED SO AS TO REPRODUCE THE THERMAL
CAPTURE CROSS SECTION AND THE NEUTRON RESONANCE CAPTURE
INTEGRAL MENTIONED ABOVE. RADIATION WIDTHS AND SCATTERING
RADIUS WERE TAKEN FROM JENDL-2.
UNRESOLVED RESONANCE REGION : 0.088 KEV - 100 KEV
THE NEUTRON STRENGTH FUNCTIONS, S0, S1 AND S2 WERE CALCULATED
WITH OPTICAL MODEL CODE CASTHY/5/. THE OBSERVED LEVEL SPACING
WAS DETERMINED TO REPRODUCE THE CAPTURE CROSS SECTION
CALCULATED WITH CASTHY. THE EFFECTIVE SCATTERING RADIUS WAS
OBTAINED FROM FITTING TO THE CALCULATED TOTAL CROSS SECTION AT
100 KEV. THE RADIATION WIDTH GG WAS BASED ON THE SYSTEMATICS
OF MEASURED VALUES FOR NEIGHBORING NUCLIDES.
TYPICAL VALUES OF THE PARAMETERS AT 70 KEV:
S0 = 1.500E-4, S1 = 1.200E-4, S2 = 1.400E-4, SG = 13.5E-4,
GG = 0.100 EV, R = 5.293 FM.
CALCULATED 2200-M/S CROSS SECTIONS AND RES. INTEGRALS (BARNS)
2200 M/S RES. INTEG.
TOTAL 13.55 -
ELASTIC 4.850 -
CAPTURE 8.702 62.5
MF = 3 NEUTRON CROSS SECTIONS
BELOW 100 KEV, RESONANCE PARAMETERS WERE GIVEN.
ABOVE 100 KEV, THE SPHERICAL OPTICAL AND STATISTICAL MODEL
CALCULATION WAS PERFORMED WITH CASTHY, BY TAKING ACCOUNT OF
COMPETING REACTIONS, OF WHICH CROSS SECTIONS WERE CALCULATED
WITH PEGASUS/6/ STANDING ON A PREEQUILIBRIUM AND MULTI-STEP
EVAPORATION MODEL. THE OMP'S FOR NEUTRON GIVEN IN TABLE 1 WERE
DETERMINED BY IGARASI ET AL./7/ TO REPRODUCE A SYSTEMATIC TREND
OF THE TOTAL CROSS SECTION. THE OMP'S FOR CHARGED PARTICLES ARE
AS FOLLOWS:
PROTON = PEREY/8/
ALPHA = HUIZENGA AND IGO/9/
DEUTERON = LOHR AND HAEBERLI/10/
HELIUM-3 AND TRITON = BECCHETTI AND GREENLEES/11/
PARAMETERS FOR THE COMPOSITE LEVEL DENSITY FORMULA OF GILBERT
AND CAMERON/12/ WERE EVALUATED BY IIJIMA ET AL./13/ MORE
EXTENSIVE DETERMINATION AND MODIFICATION WERE MADE IN THE
PRESENT WORK. TABLE 2 SHOWS THE LEVEL DENSITY PARAMETERS USED
IN THE PRESENT CALCULATION. ENERGY DEPENDENCE OF SPIN CUT-OFF
PARAMETER IN THE ENERGY RANGE BELOW E-JOINT IS DUE TO GRUPPELAAR
/14/.
MT = 1 TOTAL
SPHERICAL OPTICAL MODEL CALCULATION WAS ADOPTED.
MT = 2 ELASTIC SCATTERING
CALCULATED AS (TOTAL - SUM OF PARTIAL CROSS SECTIONS).
MT = 4, 51 - 91 INELASTIC SCATTERING
SPHERICAL OPTICAL AND STATISTICAL MODEL CALCULATION WAS
ADOPTED. THE LEVEL SCHEME WAS TAKEN FROM REF./15/
NO. ENERGY(MEV) SPIN-PARITY
GR. 0.0 7/2 +
1 0.2498 5/2 +
2 0.4080 3/2 +
3 0.6082 5/2 +
4 0.7869 7/2 +
LEVELS ABOVE 0.981 MEV WERE ASSUMED TO BE OVERLAPPING.
MT = 102 CAPTURE
SPHERICAL OPTICAL AND STATISTICAL MODEL CALCULATION WITH
CASTHY WAS ADOPTED. DIRECT AND SEMI-DIRECT CAPTURE CROSS
SECTIONS WERE ESTIMATED ACCORDING TO THE PROCEDURE OF BENZI
AND REFFO/16/ AND NORMALIZED TO 1 MILLI-BARN AT 14 MEV.
THE GAMMA-RAY STRENGTH FUNCTION (1.38E-03) WAS DETERMINED FROM
THE SYSTEMATICS OF RADIATION WIDTH (0.125 EV) AND THE AVERAGE
S-WAVE RESONANCE LEVEL SPACING (90.8 EV) CALCULATED FROM THE
LEVEL DENSITY PARAMETERS.
MT = 16 (N,2N) CROSS SECTION
MT = 17 (N,3N) CROSS SECTION
MT = 22 (N,N'A) CROSS SECTION
MT = 28 (N,N'P) CROSS SECTION
MT = 32 (N,N'D) CROSS SECTION
MT = 33 (N,N'T) CROSS SECTION
MT =103 (N,P) CROSS SECTION
MT =104 (N,D) CROSS SECTION
MT =105 (N,T) CROSS SECTION
MT =107 (N,ALPHA) CROSS SECTION
THESE REACTION CROSS SECTIONS WERE CALCULATED WITH THE
PREEQUILIBRIUM AND MULTI-STEP EVAPORATION MODEL CODE PEGASUS.
THE KALBACH'S CONSTANT K (= 408.0) WAS ESTIMATED BY THE
FORMULA DERIVED FROM KIKUCHI-KAWAI'S FORMALISM/17/ AND LEVEL
DENSITY PARAMETERS.
FINALLY, THE (N,P) AND (N,ALPHA) CROSS SECTIONS WERE
NORMALIZED TO THE FOLLOWING VALUES AT 14.5 MEV:
(N,P) 2.81 MB (SYSTEMATICS OF FORREST/18/)
(N,ALPHA) 1.41 MB (SYSTEMATICS OF FORREST)
MT = 251 MU-BAR
CALCULATED WITH CASTHY/5/.
MF = 4 ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS
LEGENDRE POLYNOMIAL COEFFICIENTS FOR ANGULAR DISTRIBUTIONS ARE
GIVEN IN THE CENTER-OF-MASS SYSTEM FOR MT=2 AND DISCRETE INELAS-
TIC LEVELS, AND IN THE LABORATORY SYSTEM FOR MT=91. THEY WERE
CALCULATED WITH CASTHY. FOR OTHER REACTIONS, ISOTROPIC DISTRI-
BUTIONS IN THE LABORATORY SYSTEM WERE ASSUMED.
MF = 5 ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS
ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS WERE CALCULATED WITH
PEGASUS FOR INELASTIC SCATTERING TO OVERLAPPING LEVELS AND FOR
OTHER NEUTRON EMITTING REACTIONS.
TABLE 1 NEUTRON OPTICAL POTENTIAL PARAMETERS
DEPTH (MEV) RADIUS(FM) DIFFUSENESS(FM)
---------------------- ------------ ---------------
V = 46.0-0.25E R0 = 6.551 A0 = 0.62
WI = 0.125E-0.0004E**2 RI = 6.551 AI = 0.62
WS = 7.0 RS = 7.051 AS = 0.35
VSO= 7.0 RSO= 6.551 ASO= 0.62
THE FORM OF SURFACE ABSORPTION PART IS DER. WOODS-SAXON TYPE.
TABLE 2 LEVEL DENSITY PARAMETERS
NUCLIDE A(1/MEV) T(MEV) C(1/MEV) EX(MEV) PAIRING
---------------------------------------------------------------
53-I -131 1.600E+01 6.330E-01 2.958E+00 5.342E+00 1.040E+00
53-I -132 1.550E+01 6.000E-01 8.595E+00 3.552E+00 0.0
53-I -133 1.559E+01 4.890E-01 7.662E-01 2.691E+00 7.000E-01
53-I -134 1.500E+01 5.600E-01 4.764E+00 2.769E+00 0.0
54-XE-132 1.563E+01 6.500E-01 5.485E-01 6.600E+00 2.160E+00
54-XE-133 1.600E+01 6.250E-01 2.327E+00 5.284E+00 1.120E+00
54-XE-134 1.400E+01 6.300E-01 3.184E-01 5.224E+00 1.820E+00
54-XE-135 1.550E+01 5.565E-01 7.506E-01 4.010E+00 1.120E+00
55-CS-133 1.750E+01 6.000E-01 3.784E+00 5.352E+00 1.040E+00
55-CS-134 1.598E+01 6.450E-01 1.710E+01 4.505E+00 0.0
55-CS-135 1.343E+01 6.537E-01 1.831E+00 4.203E+00 7.000E-01
55-CS-136 1.400E+01 6.000E-01 4.424E+00 2.967E+00 0.0
---------------------------------------------------------------
SPIN CUTOFF PARAMETERS WERE CALCULATED AS 0.146*SQRT(A)*A**(2/3).
IN THE CASTHY CALCULATION, SPIN CUTOFF FACTORS AT 0 MEV WERE
ASSUMED TO BE 4.75 FOR CS-135 AND 5.0 FOR CS-136.
REFERENCES
1) AOKI, T. ET AL.: PROC. INT. CONF. ON NUCLEAR DATA FOR BASIC
AND APPLIED SCIENCE, SANTA FE., VOL. 2, P.1627 (1985).
2) KAWAI, M. ET AL.: PROC. INT. CONF. ON NUCLEAR DATA FOR SCIENCE
AND TECHNOLOGY, MITO, P. 569 (1988).
3) PRIESMEYER, H.G., ET AL.: NEANDC(E)212U, VOL. V., 41 (1980).
4) MUGHABGHAB, S.F. ET AL.: "NEUTRON CROSS SECTIONS, VOL. I,
PART A", ACADEMIC PRESS (1981).
5) IGARASI, S.: J. NUCL. SCI. TECHNOL., 12, 67 (1975).
6) IIJIMA, S. ET AL.: JAERI-M 87-025, P. 337 (1987).
7) IGARASI, S. ET AL.: JAERI-M 5752 (1974).
8) PEREY, F.G: PHYS. REV. 131, 745 (1963).
9) HUIZENGA, J.R. AND IGO, G.: NUCL. PHYS. 29, 462 (1962).
10) LOHR, J.M. AND HAEBERLI, W.: NUCL. PHYS. A232, 381 (1974).
11) BECCHETTI, F.D., JR. AND GREENLEES, G.W.: POLARIZATION
PHENOMENA IN NUCLEAR REACTIONS ((EDS) H.H. BARSHALL AND
W. HAEBERLI), P. 682, THE UNIVERSITY OF WISCONSIN PRESS.
(1971).
12) GILBERT, A. AND CAMERON, A.G.W.: CAN. J. PHYS., 43, 1446
(1965).
13) IIJIMA, S., ET AL.: J. NUCL. SCI. TECHNOL. 21, 10 (1984).
14) GRUPPELAAR, H.: ECN-13 (1977).
15) LEDERER, C.M., ET AL.: "TABLE OF ISOTOPES, 7TH ED.", WILEY-
INTERSCIENCE PUBLICATION (1978).
16) BENZI, V. AND REFFO, G.: CCDN-NW/10 (1969).
17) KIKUCHI, K. AND KAWAI, M.: "NUCLEAR MATTER AND NUCLEAR
REACTIONS", NORTH HOLLAND (1968).
18) FORREST, R.A.: AERE-R 12419 (1986).