54-Xe-128 JAEA EVAL-FEB22 S.Kunieda, A.Ichihara, K.Shibata+
DIST-MAY10 20100316
----JENDL-4.0 MATERIAL 5437
-----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 1.7 keV
The parameters were mainly taken from JENDL-3.3. A resona-
nce was added at 3441.3 eV. The capture width of a negative
resonance was changed to 60.3 meV so as to reproduce the
capture cross section recommended by Mughabghab/1/.
The JENDL-3.3 evaluations is as follows:
***** JENDL-3.3 evaluation ********************************
Resonance parameters were based on the data given by
Mughabghab et al./2/, except neutron width of the 3rd
level which was derived from the value of g*(reduced neutron
width) estimated on the basis of the systematics of those
for neighboring levels. Radiation width of 66 meV for the
1st level was obtained from the total and neutron widths.
Average radiation width of 70 meV close to that of the 1st
level was adopted for the other levels. Neutron orbital
angular momentum l was assumed to be 0 for all resonance
levels. A negative resonance was added at -100 eV so as to
reproduce the thermal capture cross section given by
Mughabghab et al. Scattering radius was taken from the
graph (fig. 1, Part A) given in ref./2/.
************************************************************
- Unresolved resonance region: 1.7 keV - 300 keV
The parameters were obtained by fitting to the total and
capture cross sections calculated by the POD code /3/.
The ASREP code /4/ 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 1.62385E+01
Elastic 1.10340E+01
n,gamma 5.20447E+00 1.11142E+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 /5/ & POD /3/ calculations.
MT= 3 Non-elastic cross section
Sum of partial non-elastic cross sections.
MT= 4,51-91 (n,n') cross section
The OPTMAN /5/ & POD /3/ 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 /3/.
MT=102 Capture cross section
Calculated by the POD code /3/. The value of gamma-ray
strength function was determined to reproduce experimental
capture cross sections measured by Reifarth et al /6/.
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 /3/.
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 /3/.
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 /5/ & POD /3/ 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 /3/.
MT= 51-90 (n,n') reaction
Neutron angular distributions calculated by
OPTMAN /5/ & POD /3/.
MT= 91 (n,n') reaction
Neutron spectra calculated by the POD code /3/.
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 /3/.
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 /3/.
***************************************************************
* Nuclear Model Calculations with POD Code /3/ *
***************************************************************
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 /5/ was employed for neutrons, while the ECIS code
/7/ was adopted for charged particles.
2. Optical model & parameters
Neutrons:
Model: The coupled-channel method based on the rigid-rotor
model was adopted. Deformation parameter beta2 was
taken from ref./8/
OMP : Coupled-channel optical potential /9/ was applied.
Protons:
Model: Spherical
OMP : Koning and Delaroche /10/
Deuterons:
Model: Spherical
OMP : Bojowald et al. /11/
Tritons:
Mode: Spherical
OMP : Becchetti and Greenlees /12/
He-3:
Model: Spherical
OMP : Becchetti and Greenlees /12/
Alphas:
Model: Spherical
OMP : A simplified folding model potential /13/
(The nucleon OMP was taken from Ref./9/.)
3. Level scheme of Xe-128
------------------------------------
No. Ex(MeV) J PI CC
------------------------------------
0 0.00000 0 + *
1 0.44291 2 + *
2 0.96947 2 +
3 1.03315 4 + *
4 1.42956 3 +
5 1.58297 0 +
6 1.60341 4 +
7 1.73704 6 + *
8 1.87732 0 +
9 1.99655 5 +
10 1.99965 2 +
11 2.12706 2 -
12 2.22903 5 -
13 2.25289 4 +
14 2.27285 2 +
15 2.28090 6 -
16 2.36180 1 +
17 2.42108 3 +
18 2.43069 1 +
19 2.44392 4 +
20 2.48251 2 +
21 2.50077 5 -
22 2.51071 2 +
23 2.51254 8 +
24 2.52137 4 -
25 2.55067 2 +
26 2.56478 0 +
27 2.58317 5 -
28 2.59157 1 +
29 2.59858 0 +
30 2.63300 2 +
------------------------------------
Levels above 2.64300 MeV are assumed to be continuous.
4. Level density parameters
Energy-dependent parameters of Mengoni-Nakajima /14/ were used
----------------------------------------------------------
Nuclei a* Pair Esh T E0 Ematch Elv_max
1/MeV MeV MeV MeV MeV MeV MeV
----------------------------------------------------------
Xe-129 16.580 1.057 0.970 0.676 -1.490 7.279 0.589
Xe-128 15.820 2.121 1.127 0.604 0.631 6.688 1.430
Xe-127 16.373 1.065 1.792 0.646 -1.332 6.940 0.530
Xe-126 15.610 2.138 1.767 0.603 0.517 6.851 1.867
I -128 16.654 0.000 0.643 0.666 -2.328 5.906 0.345
I -127 15.054 1.065 1.076 0.698 -1.170 7.021 0.375
I -126 15.530 0.000 1.628 0.670 -2.309 5.892 0.146
Te-126 16.022 2.138 0.369 0.688 -0.104 8.045 2.182
Te-125 17.306 1.073 1.254 0.571 -0.575 5.652 1.089
Te-124 15.190 2.155 1.314 0.681 -0.046 7.968 2.521
----------------------------------------------------------
5. Gamma-ray strength functions
M1, E2: Standard Lorentzian (SLO)
E1 : Generalized Lorentzian (GLO) /15/
6. Preequilibrium process
Preequilibrium is on for n, p, d, t, He-3, and alpha.
Preequilibrium capture is on.
References
1) S.F.Mughabghab, "Atlas of Neutron Resonances",
Elsevier (2006).
2) Mughabghab, S.F. et al.: "Neutron Cross Sections, Vol. I,
Part A", Academic Press (1981).
3) A.Ichihara et al., JAEA-Data/Code 2007-012 (2007).
4) Y.Kikuchi et al., JAERI-Data/Code 99-025 (1999)
[in Japanese].
5) E.Soukhovitski et al., JAERI-Data/Code 2005-002 (2005).
6) Reifarth et al., Phys. Rev. C66, 064603 (2002).
7) J.Raynal, CEA Saclay report, CEA-N-2772 (1994).
8) S.Raman et al., At. Data and Nucl. Data Tables 78, 1 (1995)
9) S.Kunieda et al., J. Nucl. Sci. Technol. 44, 838 (2007).
10) A.J.Koning, J.P.Delaroche, Nucl. Phys. A713, 231 (2003).
11) Bojowald et al., Phys. Rev. C 38, 1153 (1988).
12) F.D.Becchetti,Jr., G.W.Greenlees, "Polarization
Phenomena in Nuclear Reactions," p.682, The University
of Wisconsin Press (1971).
13) D.G.Madland, NEANDC-245 (1988), p. 103.
14) A.Mengoni, Y.Nakajima, J. Nucl. Sci. Technol. 31, 151
(1994).
15) M.Brink, Ph.D thesis, Oxford University, 1955.