50-Sn-120
50-Sn-120 JAEA EVAL-Dec09 N.Iwamoto,K.Shibata
DIST-MAY10 20100119
----JENDL-4.0 MATERIAL 5049
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
History
09-12 The resolved resonance parameters were evaluated by
K.Shibata.
The data above the resolved resonance region were evaluated
and compiled by N.Iwamoto.
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 70 keV
In JENDL-3.3, resonance parameters were based on Mughabghab
et al./1/ Total spin J of J-unknown p-wave resonances was
assumed to be 1/2. Neutron orbital angular momentum L of
some resonances was estimated with a method of Bollinger and
Thomas/2/. Average radiation width of 120 meV was deduced
and applied to the levels whose radiation width was unknown.
Scattering radius of 6.0 fm was assumed from the systematics
of measured values for neighboring nuclides. A negative
resonance was added so as to reproduce the thermal capture
and scattering cross sections given by Mughabghab et al.
In JENDL-4, the data for -612 eV - 55 keV were replaced with
the obtained by Koehler et al./3/ A radius of 6.15 fm was
used. The levels at 67 and 105 eV were removed.
Unresolved resonance region : 70 keV - 200 keV
The unresolved resonance paramters (URP) were determined by
ASREP code /4/ so as to reproduce the evaluated total and
capture cross sections calculated with optical model code
OPTMAN /5/ and CCONE /6/. The unresolved parameters
should be used only for self-shielding calculation.
Thermal cross sections and resonance integrals at 300 K
----------------------------------------------------------
0.0253 eV res. integ. (*)
(barn) (barn)
----------------------------------------------------------
Total 5.3807e+00
Elastic 5.2377e+00
n,gamma 1.4299e-01 1.1415e+00
----------------------------------------------------------
(*) 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
Obtained by subtracting non-elastic scattering cross sections
from total cross section.
MT= 4 (n,n') cross section
Calculated with CCONE code /6/.
MT= 16 (n,2n) cross section
Calculated with CCONE code /6/.
MT= 17 (n,3n) cross section
Calculated with CCONE code /6/.
MT= 22 (n,na) cross section
Calculated with CCONE code /6/.
MT= 28 (n,np) cross section
Calculated with CCONE code /6/.
MT= 51-91 (n,n') cross section
Calculated with CCONE code /6/.
MT=102 Capture cross section
Calculated with CCONE code /6/.
MT=103 (n,p) cross section
Calculated with CCONE code /6/.
MT=104 (n,d) cross section
Calculated with CCONE code /6/.
MT=105 (n,t) cross section
Calculated with CCONE code /6/.
MT=106 (n,He3) cross section
Calculated with CCONE code /6/.
MT=107 (n,a) cross section
Calculated with CCONE code /6/.
MF= 4 Angular distributions of emitted neutrons
MT= 2 Elastic scattering
Calculated with CCONE code /6/.
MF= 6 Energy-angle distributions of emitted particles
MT= 16 (n,2n) reaction
Calculated with CCONE code /6/.
MT= 17 (n,3n) reaction
Calculated with CCONE code /6/.
MT= 22 (n,na) reaction
Calculated with CCONE code /6/.
MT= 28 (n,np) reaction
Calculated with CCONE code /6/.
MT= 51-91 (n,n') reaction
Calculated with CCONE code /6/.
MT=102 Capture reaction
Calculated with CCONE code /6/.
*****************************************************************
Nuclear Model Calculation with CCONE code /6/
*****************************************************************
Models and parameters used in the CCONE calculation
1) Optical model
* coupled channels calculation
coupled levels: 0,1,10 (see Table 1)
* optical model potential
neutron omp: Kunieda,S. et al./7/ (+)
proton omp: Kunieda,S. et al./7/
deuteron omp: Lohr,J.M. and Haeberli,W./8/
triton omp: Becchetti Jr.,F.D. and Greenlees,G.W./9/
He3 omp: Becchetti Jr.,F.D. and Greenlees,G.W./9/
alpha omp: Huizenga,J.R. and Igo,G./10/
(+) omp parameters were modified.
2) Two-component exciton model/11/
* Global parametrization of Koning-Duijvestijn/12/
was used.
* Gamma emission channel/13/ was added to simulate direct
and semi-direct capture reaction.
3) Hauser-Feshbach statistical model
* Width fluctuation correction/14/ was applied.
* Neutron, proton, deuteron, triton, He3, alpha and gamma
decay channel were taken into account.
* Transmission coefficients of neutrons were taken from
optical model calculation.
* The level scheme of the target is shown in Table 1.
* Level density formula of constant temperature and Fermi-gas
model were used with shell energy correction/15/.
Parameters are shown in Table 2.
* Gamma-ray strength function of generalized Lorentzian form
/16/,/17/ was used for E1 transition.
For M1 and E2 transitions the standard Lorentzian form was
adopted. The prameters are shown in Table 3.
------------------------------------------------------------------
Tables
------------------------------------------------------------------
Table 1. Level Scheme of Sn-120
-------------------
No. Ex(MeV) J PI
-------------------
0 0.00000 0 + *
1 1.17127 2 + *
2 1.87511 0 +
3 2.09721 2 +
4 2.15993 0 +
5 2.17300 2 +
6 2.19430 4 +
7 2.28427 5 -
8 2.29700 1 +
9 2.35538 2 +
10 2.40030 3 - *
11 2.42090 2 +
12 2.46563 4 +
13 2.48163 7 -
14 2.54000 5 -
15 2.58725 0 +
16 2.64335 4 +
17 2.68516 6 +
18 2.69100 4 -
19 2.69594 4 -
20 2.72812 2 +
21 2.74971 6 -
22 2.75100 4 +
23 2.80005 5 -
24 2.80200 7 -
25 2.83539 1 +
26 2.83652 8 +
27 2.84434 6 -
28 2.85761 0 +
29 2.90222 10 +
30 2.93053 2 +
-------------------
*) Coupled levels in CC calculation
Table 2. Level density parameters
--------------------------------------------------------
Nuclide a* Pair Eshell T E0 Ematch
1/MeV MeV MeV MeV MeV MeV
--------------------------------------------------------
Sn-121 14.9000 1.0909 0.9681 0.6514 -0.5137 5.5290
Sn-120 14.7000 2.1909 0.8820 0.6695 0.4967 6.8161
Sn-119 15.8000 1.1000 1.4670 0.5796 -0.2200 4.8655
Sn-118 14.7649 2.2094 1.1802 0.6386 0.7048 6.4391
In-120 14.9043 0.0000 1.9246 0.6079 -1.4610 4.0000
In-119 14.2400 1.1000 2.1477 0.6266 -0.3980 5.1833
In-118 14.6950 0.0000 2.5427 0.5650 -1.1604 3.4261
In-117 14.0356 1.1094 2.5136 0.6228 -0.3934 5.1460
Cd-119 15.5394 1.1000 2.5578 0.6443 -1.1874 6.1408
Cd-118 14.7649 2.2094 2.3367 0.6412 0.3136 6.8030
Cd-117 16.7000 1.1094 2.9235 0.6001 -1.1587 5.9328
Cd-116 14.5525 2.2283 2.7100 0.6353 0.3516 6.7335
Cd-115 16.4000 1.1190 3.1141 0.5877 -0.9615 5.6632
--------------------------------------------------------
Table 3. Gamma-ray strength function for Sn-121
--------------------------------------------------------
* E1: ER = 15.37 (MeV) EG = 5.10 (MeV) SIG = 285.00 (mb)
ER = 6.40 (MeV) EG = 1.80 (MeV) SIG = 1.50 (mb)
* M1: ER = 8.29 (MeV) EG = 4.00 (MeV) SIG = 1.18 (mb)
* E2: ER = 12.74 (MeV) EG = 4.66 (MeV) SIG = 2.64 (mb)
--------------------------------------------------------
References
1) Mughabghab, S.F. et al.: "Neutron Cross Sections, Vol. I,
Part A", Academic Press (1981).
2) Bollinger, L.M., Thomas, G.E.: Phys. Rev., 171,1293(1968).
3) Koehler, P.E. et al.: Phys. Rev., C64, 065802 (2001).
4) Kikuchi,Y. et al.: JAERI-Data/Code 99-025 (1999)
[in Japanese].
5) Soukhovitski,E.Sh. et al.: JAERI-Data/Code 2005-002 (2004).
6) Iwamoto,O.: J. Nucl. Sci. Technol., 44, 687 (2007).
7) Kunieda,S. et al.: J. Nucl. Sci. Technol. 44, 838 (2007).
8) Lohr,J.M. and Haeberli,W.: Nucl. Phys. A232, 381 (1974).
9) Becchetti Jr.,F.D. and Greenlees,G.W.: Ann. Rept.
J.H.Williams Lab., Univ. Minnesota (1969).
10) Huizenga,J.R. and Igo,G.: Nucl. Phys. 29, 462 (1962).
11) Kalbach,C.: Phys. Rev. C33, 818 (1986).
12) Koning,A.J., Duijvestijn,M.C.: Nucl. Phys. A744, 15 (2004).
13) Akkermans,J.M., Gruppelaar,H.: Phys. Lett. 157B, 95 (1985).
14) Moldauer,P.A.: Nucl. Phys. A344, 185 (1980).
15) Mengoni,A. and Nakajima,Y.: J. Nucl. Sci. Technol., 31, 151
(1994).
16) Kopecky,J., Uhl,M.: Phys. Rev. C41, 1941 (1990).
17) Kopecky,J., Uhl,M., Chrien,R.E.: Phys. Rev. C47, 312 (1990).