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51-Sb-121 JNDC EVAL-AUG89 JNDC FP NUCLEAR DATA W.G.
DIST-JAN09 20090105
----JEFF-311 MATERIAL 5125
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
*************************** JEFF-3.1.1 *************************
** **
** Original data taken from: JEFF-3.1 **
** **
******************************************************************
***************************** JEFF-3.1 *************************
** **
** Original data taken from: JENDL-3.3 **
** **
******************************************************************
HISTORY
84-10 Evaluation for JENDL-2 was made by JNDC FPND W.G./1/
89-08 Modification for JENDL-3 was made/2/.
94-02 JENDL-3.2
Capture cross section modified by JNDC FPND WG.
Other data were adopted from JENDL fusion file.
Compiled by T.Nakagawa
***** modified parts for JENDL-3.2 ********************
All cross sections except (3,105).
(3,32) and (3,33) were deleted.
All angular distributions except for (4,2).
All energy distributions.
***********************************************************
-------------------------------------------------------------
JENDL fusion file /3/ (as of Feb. 1994)
Evaluated by K.Kosako (nedac) and S. Chiba (ndc/jaeri)
Compiled by K.Kosako.
- The inelastic scattering cross sections and angular
distributions of inelastically scattered neutrons (except
continuum inelastic) were calculated with casthy2y and
dwucky in sincros-ii system/4/ including contributions
from direct reactions.
- The (n,2n), (n,3n), (n,na), (n,np), (n,p), (n,d) and
(n,a) reaction cross sections (mt=16, 17, 22, 28, 103,
104, 107) were calculated by egnash2 in the sincros-ii.
- The (n,t) reaction cross section, resonance parameters
and ang. distributions of elastically scattered neutrons
were taken from JENDL-3.1.
- Energy distributions of secondary neutrons were replaced
by those calculated by egnash2. The ddx's of the
continuum neutrons were calculated by Kumabe's systema-
tics /5/ using f15tob /3/. The precompound/compound
ratio was calculated by the sincros- ii code system.
- Optical-model, level density and other parameters used in
the sincros-ii calculation are described in ref./4/.
Level schemes were determined on the basis of ENSDF/6/.
-------------------------------------------------------------
01-07 JENDL-3.3
Compiled by K.Shibata
***** modified parts for JENDL-3.3 *********************
(1,451) Updated.
(3,251) Deleted.
(4,2) Transformation matrix deleted.
(4,16-28) Deleted.
(4,91) Deleted.
(5,16-91) Deleted.
(6,16-207) Taken from JENDL fusion file
************************************************************
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 2 keV
Resonance parameters of JENDL-2/1/ were revised except for
radiation widths.
Evaluation of JENDL-2 was made on the basis of the data
measured by Bolotin and Chrien/7/, Wynchank et al./8/,
Muradjan et al./9/, Adamchuk et al./10/ and Ohkubo et al.
/11/ Neutron orbital angular momentum L and total spin J
were based on the data by Bhat et al./12/ and Cauvin et al.
/13/ The average radiation width of 0.089 eV was deduced and
applied to the levels whose radiation width was unknown.
After that, new experimental data for neutron widths and
total spin J were published by Ohkubo et al./14/ and Beliaev
et al./15/, respectively.
Evaluation of JENDL-3 was performed on the basis of the
new data for the neutron widths and spin J and JENDL-2 for
the radiation widths. Total spin J of some resonances was
tentatively estimated with a random number method. Neutron
orbital angular momentum L was estimated with a method of
Bollinger and Thomas/16/. Scattering radius of 6.0 fm was
assumed from the systematics of measured values for
neighboring nuclides.
Unresolved resonance region : 2 keV - 100 keV
The neutron strength function S0 was based on the compilation
of Mughabghab et al./17/, and S1 and S2 were calculated with
optical model code casthy/18/. 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 was based on the compilation of Mughabghab
et al.
Typical values of the parameters at 70 keV:
S0 = 0.300e-4, S1 = 2.700e-4, S2 = 0.760e-4, Sg = 59.8e-4,
Gg = 0.100 ev, R = 5.838 fm.
calculated 2200-m/s cross sections and res. integrals (barns)
2200 m/s res. integ.
total 9.582 -
elastic 3.590 -
capture 5.991 214
mf = 3 Neutron cross sections
Below 100 keV, resonance parameters were given.
For JENDL-3.1, 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/19/ standing on a preequilibrium
and multi-step evaporation model. The omp's for neutron given
in table 1 were determined so as to reproduce a systematic trend
of the total cross section by changing rso of Iijima-Kawai
potential/20/. The omp's for charged particles are as follows:
proton = Perey/21/
alpha = Huizenga and igo/22/
deuteron = Lohr and Haeberli/23/
helium-3 and triton = Becchetti and Greenlees/24/
Parameters for the composite level density formula of Gilbert
and Cameron/25/ were evaluated by Iijima et al./26/ 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
/27/.
For JENDL-3.2, all cross section data except for the elastic
scattering, capture and (n,t) were adopted from JENDL fusion
file. The calculation was made with sincros-ii system/4/ by
adopting Walter-Guss omp modified by Yamamuro/4/ for neutron,
Perey omp /28/ for Proton, Lemos omp modified by Arthur and
Young/29/ for alpha, Lohr-Haeberli omp/30/ for deuteron,
Becchettii-Greenlees omp/24/ for triton and he-3, and standard
level density parameters of sincros-ii system.
mt = 1 Total
Spherical optical model calculation with the modified Walter-
Guss omp/4/ was adopted.
mt = 2 Elastic scattering
Calculated as (total - sum of partial cross sections).
mt = 4, 51 - 91 Inelastic scattering
The cross sections were taken from JENDL fusion file. The
level scheme was based on ref./6/ Contributions of the
direct process were calculated for the levels marked with '*'.
no. energy(MeV) spin-parity (direct process)
gr. 0.0 5/2 +
1 0.0371 7/2 + *
2 0.5076 3/2 + *
3 0.5731 1/2 + *
4 0.9470 9/2 + *
5 1.0240 7/2 + *
6 1.0354 9/2 +
7 1.1393 11/2 +
8 1.1447 7/2 + *
9 1.3862 9/2 +
10 1.4075 5/2 +
11 1.4105 7/2 +
12 1.4272 9/2 + *
13 1.4480 1/2 -
Levels above 1.449 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/31/ and normalized to 1 milli-barn at 14 MeV.
The gamma-ray strength function (54.5e-4) was adjusted to
reproduce the capture cross section of 110 milli-barns at 1
MeV which was an average value of experimental data of
Trofimov/32/ and our previous evaluation normalized to 150 mb
at 500 keV/33/.
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 =103 (n,p) cross section
mt =104 (n,d) cross section
mt =107 (n,alpha) cross section
Adopted from JENDL fusion file. Theoretical calculation was
made with sincros-ii. The results were normalized to
(n,d)+(n,np) 0.00415 b at 14.5 MeV (systematics of Forrest/34/),
(n,a) 0.0036 b at 14.9 MeV (systematics of Konno+/35/).
and the (n,2n) cross section was adjusted to the energy
distributions of emitted neutrons (a factor of 1.27 was
applied).
mt =105 (n,t) cross section
This reaction cross section was calculated with the
preequilibrium and multi-step evaporation model code pegasus.
The kalbach's constant k (= 145.3) was estimated by the
formula derived from Kikuchi-Kawai's formalism/36/ and level
density parameters.
mt=203 Total proton production
Sum of mt=28 and 103.
mt=204 Total deuteron production
Equal to mt=104.
mt=205 Total triton production
Equal to mt=105.
mt=207 Total alpha production
Sum of mt=22 and 107.
mf = 4 Angular distributions of secondary neutrons
mt=2
Calculated with the casthy code/20/.
mt=51-63
Taken from JENDL fusion file.
mf = 6 Energy-angle distributions of secondary particles
mt=16, 17, 22, 28, 91, 203, 204, 205, 207
Taken from JENDL fusion file.
<< The parameters used in the casthy and pegasus calculations. >>
Table 1 Neutron optical potential parameters
depth (MeV) radius(fm) diffuseness(fm)
---------------------- ------------ ---------------
V = 47.64-0.473E r0 = 6.256 a0 = 0.62
Ws = 9.744 rs = 6.469 as = 0.35
Vso= 7.0 rso= 6.241 aso= 0.62
The form of surface absorption part is der. Woods-Saxon type.
Table 2 Level density parameters
nuclide syst a(1/MeV) t(MeV) c(1/MeV) Ex(MeV) pairing
---------------------------------------------------------------
49-In-117 1.678e+01 6.010e-01 2.387e+00 5.208e+00 1.150e+00
49-In-118 * 1.804e+01 6.064e-01 3.111e+01 4.636e+00 0.0
49-In-119 1.940e+01 5.340e-01 2.195e+00 4.999e+00 1.240e+00
49-In-120 * 1.757e+01 6.016e-01 2.330e+01 4.366e+00 0.0
50-Sn-118 1.633e+01 6.140e-01 3.341e-01 6.448e+00 2.340e+00
50-Sn-119 1.635e+01 5.990e-01 1.772e+00 5.050e+00 1.190e+00
50-Sn-120 1.595e+01 6.540e-01 4.691e-01 7.083e+00 2.430e+00
50-Sn-121 1.630e+01 6.100e-01 2.010e+00 5.217e+00 1.190e+00
51-Sb-119 * 1.858e+01 6.040e-01 5.801e+00 5.944e+00 1.150e+00
51-Sb-120 * 1.834e+01 6.016e-01 3.366e+01 4.659e+00 0.0
51-Sb-121 1.730e+01 5.740e-01 1.715e+00 5.022e+00 1.240e+00
51-Sb-122 1.772e+01 5.500e-01 1.346e+01 3.517e+00 0.0
---------------------------------------------------------------
syst: * = ldp's were determined from systematics.
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 9.25 for Sb-121 and 5.0 for Sb-122.
References
1) Aoki, T. et al.: Proc. Int. Conf. on Nuclear Data for Basic
and Applied Science, Santa Fe., Vol. 2, p.1627 (1985).
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4) Yamamuro, N.: JAERI-M 90-006 (1990).
5) Kumabe, I. et al.: Nucl. Sci. Eng., 104, 280 (1990).
6) ENSDF: Evaluated Nuclear Structure Data File, BNL/NNDC.
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8) Wynchank, S., et al.: Phys. Rev., 166, 1234 (1968).
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24) 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).
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(1965).
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29) Arthur, E.D. and Young, P.G.: LA-8626-MS (1980).
30) Lohr, J.M. and Haeberli W.: Nucl. Phys., A232, 381 (1974).
31) Benzi, V. and Reffo, G.: CCDN-NW/10 (1969).
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1987, Vol. 3, p.331 (1987).
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34) Forrest, R.A.: AERE-R 12419 (1986).
35) Konno, C. et al.: JAERI 1329 (1993).
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Reactions", North Holland (1968).
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