48-Cd-108 JAEA EVAL-FEB22 S.Kunieda, A.Ichihara, K.Shibata+
DIST-MAY10 20100316
----JENDL-4.0 MATERIAL 4831
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
History
09-11 Re-evaluation was performed for JENDL-4.0
10-03 Compiled by S.Kunieda
MF= 1 General information
MT=451 Descriptive data and directory
MF= 2 Resonance parameters
MT=151 Resolved and unresolved resonance parameters
- Resolved resonance region (MLBW formula): below 380 eV
Resonance parameters were based on the experimental data
of Anufriev et al./1/ Neutron orbital angular momentum
L was estimated with a method of Bollinger and Thomas/2/.
Scattering radius of 6.5 fm was assumed from the systematics
of measured values for neighboring nuclides. A negative
resonance was added so as to reproduce the thermal capture
cross section given by Mughabghab et al./3/
In JENDL-3.3, R was changed from 6.5fm to 6.2fm so as to
reproduce measured elemental total cross sections.
In JENDL-4, the energy of the negative resonance was
changed to -700 eV so as to reproduce the thermal capture
cross section recommended by Mughabghab./4/
- Unresolved resonance region: 380 eV - 300 keV
The parameters were obtained by fitting to the total and
capture cross sections calculated by the POD code /5/.
The ASREP code /6/ was employed in this evaluation.
The unresolved parameters should be used only for
self-shielding calculation.
Thermal cross sections & resonance integrals at 300 K
----------------------------------------------------------
0.0253 eV res. integ. (*)
(barns) (barns)
----------------------------------------------------------
Total 5.35544E+00
Elastic 4.56867E+00
n,gamma 7.86762E-01 2.53116E+01
----------------------------------------------------------
(*) Integrated from 0.5 eV to 10 MeV.
MF= 3 Neutron cross sections
MT= 1 Total cross section
Sum of partial cross sections.
MT= 2 Elastic scattering cross section
The OPTMAN /7/ & POD /5/ calculations.
MT= 3 Non-elastic cross section
Sum of partial non-elastic cross sections.
MT= 4,51-91 (n,n') cross section
The OPTMAN /7/ & POD /5/ calculations.
MT= 16 (n,2n) cross section
MT= 17 (n,3n) cross section
MT= 22 (n,na) cross section
MT= 28 (n,np) cross section
MT= 32 (n,nd) cross section
Calculated by the POD code /5/.
MT=102 Capture cross section
Calculated by the POD code /5/. The value of gamma-ray
strength function was determined to reproduce experimental
capture cross sections measured by Musgrove et al /8/.
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,a) cross section
Calculated by the POD code /5/.
MT=203 (n,xp) cross section
Sum of (n,np) and (n,p)
MT=204 (n,xd) cross section
Sum of (n,nd) and (n,d)
MT=205 (n,xt) cross section
MT=206 (n,xHe3) cross section
Calculated by the POD code /5/.
MT=207 (n,xa) cross section
Sum of (n,na) and (n,a)
MF= 4 Angular distributions of emitted neutrons
MT= 2 Elastic scattering
The OPTMAN /7/ & POD /5/ calculations.
MF= 6 Energy-angle distributions of emitted particles
MT= 16 (n,2n) reaction
MT= 17 (n,3n) reaction
MT= 22 (n,na) reaction
MT= 28 (n,np) reaction
MT= 32 (n,nd) reaction
Neutron spectra calculated by the POD code /5/.
MT= 51-90 (n,n') reaction
Neutron angular distributions calculated by
OPTMAN /7/ & POD /5/.
MT= 91 (n,n') reaction
Neutron spectra calculated by the POD code /5/.
MT= 203 (n,xp) reaction
MT= 204 (n,xd) reaction
MT= 205 (n,xt) reaction
MT= 206 (n,xHe3) reaction
MT= 207 (n,xa) reaction
Light-ion spectra calculated by the POD code /6/.
MF=12 Gamma-ray multiplicities
MT= 3 Non-elastic gamma emission
Calculated by the POD code /5/.
MF=14 Gamma-ray angular distributions
MT= 3 Non-elastic gamma emission
Assumed to be isotropic.
MF=15 Gamma-ray spectra
MT= 3 Non-elastic gamma emission
Calculated by the POD code /5/.
***************************************************************
* Nuclear Model Calculations with POD Code /5/ *
***************************************************************
1. Theoretical models
The POD code is based on the spherical optical model, the
distorted-wave Born approximaiton (DWBA), one-component exciton
preequilibrium model, and the Hauser-Feshbach-Moldauer statis-
tical model. With the preequilibrium model, semi-empirical
pickup and knockout process can be taken into account for
composite-particle emission. The gamma-ray emission from the
compound nucleus can be calculated within the framework of the
exciton model. The code is capable of reading in particle
transmission coefficients calculated by separate spherical or
coupled-channel optical model code. In this evaluation, the OPTMAN
code /7/ was employed for neutrons, while the ECIS code
/9/ was adopted for charged particles.
2. Optical model & parameters
Neutrons:
Model: The coupled-channel method based on the soft-rotor
model was adopted. The Hamiltonian parameters were
identical to those reported in ref /10/.
OMP : Coupled-channel optical potential /11/ was applied.
The original parameters were slightly modified to give
precise reaction cross sections. The optical potential
parameters used in evaluation are listed as follows.
------------------------------------------------------------
- Real-volume term
VR0= -3.80E+1 MeV VR1= 2.70E-2 MeV VR2= 1.20E-4 MeV
VR3= 3.50E-7 MeV VRLA= 9.49E+1 MeV ALAVR= 4.33E-3
r= 1.21E+0 a= 6.30E-1
- Imaginary-surface term
WDBW= 1.30E+1 MeV WDWID= 1.50E+1 MeV ALAWD= 1.40E-2
r= 1.21E+0 a= 6.00E-1
- Imaginary-volume term
WCBW= 1.70E+1 MeV WCWID= 1.00E+2 MeV
r= 1.21E+0 a= 6.00E-1
- Spin-orbit term
VS= 6.25E+0 MeV ALASO= 5.00E-3
WSBW= -3.10E+0 MeV WSWID= 1.60E+2 MeV
r= 1.04E+0 a= 5.90E-1
- Isospin coefficients
CISO= 2.43E+1 WCISO= 1.80E+1 CCOUL= 9.00E-1
------------------------------------------------------------
Protons:
Model: Spherical
OMP : Koning and Delaroche /12/
Deuterons:
Model: Spherical
OMP : Bojowald et al. /13/
Tritons:
Mode: Spherical
OMP : Becchetti and Greenlees /14/
He-3:
Model: Spherical
OMP : Becchetti and Greenlees /14/
Alphas:
Model: Spherical
OMP : A simplified folding model potential /15/
(The nucleon OMP was taken from Ref./11/.)
3. Level scheme of Cd-108
------------------------------------
No. Ex(MeV) J PI CC
------------------------------------
0 0.00000 0 + *
1 0.63299 2 + *
2 1.50846 4 +
3 1.60184 2 +
4 1.72065 0 +
5 1.91343 0 +
6 2.14585 3 +
7 2.16272 2 +
8 2.20222 3 - *
9 2.23935 4 +
10 2.36577 2 +
11 2.37456 0 +
12 2.48630 2 +
13 2.54138 6 +
14 2.55523 2 +
15 2.56522 5 +
16 2.60165 5 -
17 2.61997 2 +
18 2.64562 4 +
19 2.67799 1 -
------------------------------------
Levels above 2.68799 MeV are assumed to be continuous.
4. Level density parameters
Energy-dependent parameters of Mengoni-Nakajima /16/ were used
----------------------------------------------------------
Nuclei a* Pair Esh T E0 Ematch Elv_max
1/MeV MeV MeV MeV MeV MeV MeV
----------------------------------------------------------
Cd-109 15.088 1.149 1.603 0.656 -0.917 6.585 1.173
Cd-108 13.699 2.309 0.690 0.771 -0.106 8.748 2.678
Cd-107 15.000 1.160 0.354 0.718 -1.112 7.146 0.999
Cd-106 13.484 2.331 -0.596 0.872 -0.570 9.864 2.492
Ag-108 14.291 0.000 2.527 0.662 -2.137 5.542 0.408
Ag-107 13.008 1.160 1.978 0.773 -1.460 7.846 1.147
Ag-106 13.429 0.000 1.253 0.756 -2.357 6.276 0.809
Pd-106 13.484 2.331 2.347 0.713 0.011 8.343 2.485
Pd-105 14.058 1.171 2.073 0.743 -1.698 7.986 0.808
Pd-104 13.269 2.353 1.161 0.810 -0.541 9.540 2.245
----------------------------------------------------------
5. Gamma-ray strength functions
M1, E2: Standard Lorentzian (SLO)
E1 : Generalized Lorentzian (GLO) /17/
6. Preequilibrium process
Preequilibrium is on for n, p, d, t, He-3, and alpha.
Preequilibrium capture is on.
References
1) Anufriev, V.A. et al.: Atomnaya Energiya, 57, 59 (1984).
2) Bollinger, L.M. and Thomas, G.E.: Phys. Rev., 171,1293(1968).
3) Mughabghab, S.F. et al.: "Neutron Cross Sections, Vol. I,
Part A", Academic Press (1981).
4) S.F.Mughabghab, "Atlas of Neutron Resonances",
Elsevier (2006).
5) A.Ichihara et al., JAEA-Data/Code 2007-012 (2007).
6) Y.Kikuchi et al., JAERI-Data/Code 99-025 (1999)
[in Japanese].
7) E.Soukhovitski et al., JAERI-Data/Code 2005-002 (2005).
8) Musgrove, A.R. de L., et al.: J. Phsics pt G, 4, 771 (1978).
9) J.Raynal, CEA Saclay report, CEA-N-2772 (1994).
10) S.Kunieda et al., J. Nucl. Sci. Technol. 46, 914 (2009).
11) S.Kunieda et al., J. Nucl. Sci. Technol. 44, 838 (2007).
12) A.J.Koning, J.P.Delaroche, Nucl. Phys. A713, 231 (2003).
13) Bojowald et al., Phys. Rev. C 38, 1153 (1988).
14) F.D.Becchetti,Jr., G.W.Greenlees, "Polarization
Phenomena in Nuclear Reactions," p.682, The University
of Wisconsin Press (1971).
15) D.G.Madland, NEANDC-245 (1988), p. 103.
16) A.Mengoni, Y.Nakajima, J. Nucl. Sci. Technol. 31, 151
(1994).
17) M.Brink, Ph.D thesis, Oxford University, 1955.