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41-Nb- 95 JNDC EVAL-MAR90 JNDC FP NUCLEAR DATA W.G.
DIST-JAN09 20090105
----JEFF-311 MATERIAL 4131
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
** **
** Original data taken from: JEFF-3.1 **
** **
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***************************** JEFF-3.1 *************************
** **
** Original data taken from: JENDL-3.3 **
** **
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JENDL-3.2 data were automatically transformed to JENDL-3.3.
Interpolation of spectra: 22 (unit base interpolation)
(3,251) deleted, T-matrix of (4,2) deleted, and others.
===========================================================
HISTORY
90-03 NEW EVALUATION FOR JENDL-3 WAS COMPLETED BY JNDC FPND
W.G./1/
MF = 1 GENERAL INFORMATION
MT=451 COMMENTS AND DICTIONARY
MF = 2 RESONANCE PARAMETERS
MT=151 RESOLVED AND UNRESOLVED RESONANCE PARAMETERS
NO RESOLVED RESONANCE PARAMETERS
UNRESOLVED RESONANCE REGION : 25 EV - 100 KEV
THE NEUTRON STRENGTH FUNCTIONS, S0, S1 AND S2 WERE CALCULATED
WITH OPTICAL MODEL CODE CASTHY/2/. 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 SYSTEMATIC OF
MEASURED VALUES FOR NEIGHBORING NUCLIDES.
TYPICAL VALUES OF THE PARAMETERS AT 70 KEV:
S0 = 0.370E-4, S1 = 5.500E-4, S2 = 0.360E-4, SG = 33.8E-4,
GG = 0.160 EV, R = 6.700 FM.
CALCULATED 2200-M/S CROSS SECTIONS AND RES. INTEGRALS (BARNS)
2200 M/S RES. INTEG.
TOTAL 12.70 -
ELASTIC 5.700 -
CAPTURE 7.000 41.8
MF = 3 NEUTRON CROSS SECTIONS
BELOW 25 EV, THE CAPTURE AND ELASTIC SCATTERING CROSS SECTIONS
WERE ASSUMED TO BE IN 1/V FORM AND CONSTANT, RESPECTIVELY.
THE CAPTURE CROSS SECTION AT 0.0253 EV WAS ADOPTED FROM REF./3/
AND THE SCATTERING CROSS SECTION WAS CALCULATED FROM R = 6.7 FM.
UNRESOLVED RESONANCE PARAMETERS WERE GIVEN IN THE ENERGY RANGE
FROM 25 EV TO 100 KEV.
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/4/ STANDING ON A PREEQUILIBRIUM AND MULTI-STEP
EVAPORATION MODEL. THE OMP'S FOR NEUTRON GIVEN IN TABLE 1 WERE
DETERMINED BY IIJIMA AND KAWAI/5/ TO REPRODUCE A SYSTEMATIC
TREND OF THE TOTAL CROSS SECTION. THE OMP'S FOR CHARGED
PARTICLES ARE AS FOLLOWS:
PROTON = PEREY/6/
ALPHA = HUIZENGA AND IGO/7/
DEUTERON = LOHR AND HAEBERLI/8/
HELIUM-3 AND TRITON = BECCHETTI AND GREENLEES/9/
PARAMETERS FOR THE COMPOSITE LEVEL DENSITY FORMULA OF GILBERT
AND CAMERON/10/ WERE EVALUATED BY IIJIMA ET AL./11/ 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
/12/.
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 BASED ON EVALUATED NUCLEAR
STRUCTURE DATA FILE (1987 VERSION)/13/ AND NUCLEAR DATA
SHEETS/14/.
NO. ENERGY(MEV) SPIN-PARITY
GR. 0.0 9/2 +
1 0.2357 1/2 -
2 0.7242 7/2 +
3 0.7280 3/2 +
4 0.7567 7/2 +
5 0.7990 1/2 -
6 1.0000 5/2 -
7 1.0880 7/2 -
8 1.2230 1/2 -
9 1.2740 1/2 -
10 1.4190 7/2 -
11 1.5140 7/2 -
12 1.5900 3/2 +
13 1.6450 3/2 +
14 1.6910 3/2 +
15 1.8100 3/2 +
16 1.9130 3/2 +
17 1.9800 7/2 -
18 2.0700 3/2 +
19 2.1210 3/2 +
20 2.1650 3/2 +
LEVELS ABOVE 2.26 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/15/ AND NORMALIZED TO 1 MILLI-BARN AT 14 MEV.
THE GAMMA-RAY STRENGTH FUNCTION (3.26E-03) WAS DETERMINED FROM
THE SYSTEMATICS OF RADIATION WIDTH (0.16 EV) AND THE AVERAGE
S-WAVE RESONANCE LEVEL SPACING (49.1 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 =106 (N,HE3) 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 (= 167.0) WAS ESTIMATED BY THE
FORMULA DERIVED FROM KIKUCHI-KAWAI'S FORMALISM/16/ 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) 15.00 MB (SYSTEMATICS OF FORREST/17/)
(N,ALPHA) 4.32 MB (SYSTEMATICS OF FORREST)
MT = 251 MU-BAR
CALCULATED WITH CASTHY.
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 = 5.893 A0 = 0.62
WS = 7.0 RS = 6.393 AS = 0.35
VSO= 7.0 RSO= 5.893 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
---------------------------------------------------------------
39-Y - 91 1.050E+01 7.140E-01 8.362E-01 3.521E+00 7.200E-01
39-Y - 92 1.012E+01 7.629E-01 2.480E+00 3.191E+00 0.0
39-Y - 93 1.150E+01 8.053E-01 1.740E+00 5.854E+00 1.120E+00
39-Y - 94 9.149E+00 7.385E-01 1.378E+00 2.222E+00 0.0
40-ZR- 92 1.088E+01 8.192E-01 5.122E-01 6.429E+00 1.920E+00
40-ZR- 93 1.298E+01 7.000E-01 1.273E+00 5.183E+00 1.200E+00
40-ZR- 94 1.275E+01 7.530E-01 4.411E-01 7.019E+00 2.320E+00
40-ZR- 95 1.331E+01 6.070E-01 5.453E-01 3.985E+00 1.200E+00
41-NB- 93 1.250E+01 7.120E-01 2.205E+00 4.629E+00 7.200E-01
41-NB- 94 1.281E+01 7.230E-01 7.763E+00 4.250E+00 0.0
41-NB- 95 1.277E+01 7.500E-01 2.121E+00 5.782E+00 1.120E+00
41-NB- 96 1.331E+01 5.880E-01 3.406E+00 2.530E+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 3.625 FOR NB- 95 AND 5.0 FOR NB- 96.
REFERENCES
1) KAWAI, M. ET AL.: PROC. INT. CONF. ON NUCLEAR DATA FOR SCIENCE
AND TECHNOLOGY, MITO, P. 569 (1988).
2) IGARASI, S.: J. NUCL. SCI. TECHNOL., 12, 67 (1975).
3) MUGHABGHAB, S.F. ET AL.: "NEUTRON CROSS SECTIONS, VOL. I,
PART A", ACADEMIC PRESS (1981).
4) IIJIMA, S. ET AL.: JAERI-M 87-025, P. 337 (1987).
5) IIJIMA, S. AND KAWAI, M.: J. NUCL. SCI. TECHNOL., 20, 77
(1983).
6) PEREY, F.G: PHYS. REV. 131, 745 (1963).
7) HUIZENGA, J.R. AND IGO, G.: NUCL. PHYS. 29, 462 (1962).
8) LOHR, J.M. AND HAEBERLI, W.: NUCL. PHYS. A232, 381 (1974).
9) 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).
10) GILBERT, A. AND CAMERON, A.G.W.: CAN. J. PHYS., 43, 1446
(1965).
11) IIJIMA, S., ET AL.: J. NUCL. SCI. TECHNOL. 21, 10 (1984).
12) GRUPPELAAR, H.: ECN-13 (1977).
13) ENSDF: EVALUATED NUCLEAR STRUCTURE DATA FILE (JUNE 1987).
14) NUCLEAR DATA SHEETS, 38, 1 (1983).
15) BENZI, V. AND REFFO, G.: CCDN-NW/10 (1969).
16) KIKUCHI, K. AND KAWAI, M.: "NUCLEAR MATTER AND NUCLEAR
REACTIONS", NORTH HOLLAND (1968).
17) FORREST, R.A.: AERE-R 12419 (1986).
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