74-W -184 JAEA EVAL-Feb10 N.Iwamoto
DIST-MAY10 20100301
----JENDL-4.0 MATERIAL 7437
-----INCIDENT NEUTRON DATA
------ENDF-6 FORMAT
History
10-02 The resolved resonance parameters were evaluated by
N.Iwamoto.
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 parameters for MLBW formula were given in the energy
below 3.5 keV. Parameters were evaluated in examining both
the experimental data/1,2,3/ and the recommended
data of BNL/4/. For unknown radiative width, an average
value of 57 milli-eV was assumed. The scattering radius was
assumed to be 7.5 fm.
For JENDL-4.0 the upper limit of the resolved resonance
energy was changed due to significant level missing. The
negative resonance was placed so as to reproduce the cross
sections at thermal energy recommended by Mughabghab /5/.
Unresolved resonance region : 3.5 keV - 300 keV
The unresolved resonance paramters (URP) were determined by
ASREP code /6/ so as to reproduce the evaluated total and
capture cross sections calculated with optical model code
CCOM /7/ and CCONE /8/. 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 9.0699e+00
Elastic 7.3720e+00
n,gamma 1.6980e+00 1.6603e+01
n,alpha 3.8281e-08
----------------------------------------------------------
(*) 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 /8/.
MT= 16 (n,2n) cross section
Calculated with CCONE code /8/.
MT= 17 (n,3n) cross section
Calculated with CCONE code /8/.
MT= 22 (n,na) cross section
Calculated with CCONE code /8/.
MT= 24 (n,2na) cross section
Calculated with CCONE code /8/.
MT= 28 (n,np) cross section
Calculated with CCONE code /8/.
MT= 32 (n,nd) cross section
Calculated with CCONE code /8/.
MT= 33 (n,nt) cross section
Calculated with CCONE code /8/.
MT= 51-91 (n,n') cross section
Calculated with CCONE code /8/.
MT=102 Capture cross section
Calculated with CCONE code /8/.
MT=103 (n,p) cross section
Calculated with CCONE code /8/.
MT=104 (n,d) cross section
Calculated with CCONE code /8/.
MT=105 (n,t) cross section
Calculated with CCONE code /8/.
MT=106 (n,He3) cross section
Calculated with CCONE code /8/.
MT=107 (n,a) cross section
Calculated with CCONE code /8/.
MF= 4 Angular distributions of emitted neutrons
MT= 2 Elastic scattering
Calculated with CCONE code /8/.
MF= 6 Energy-angle distributions of emitted particles
MT= 16 (n,2n) reaction
Calculated with CCONE code /8/.
MT= 17 (n,3n) reaction
Calculated with CCONE code /8/.
MT= 22 (n,na) reaction
Calculated with CCONE code /8/.
MT= 24 (n,2na) reaction
Calculated with CCONE code /8/.
MT= 28 (n,np) reaction
Calculated with CCONE code /8/.
MT= 32 (n,nd) reaction
Calculated with CCONE code /8/.
MT= 33 (n,nt) reaction
Calculated with CCONE code /8/.
MT= 51-91 (n,n') reaction
Calculated with CCONE code /8/.
MT=102 Capture reaction
Calculated with CCONE code /8/.
*****************************************************************
Nuclear Model Calculation with CCONE code /8/
*****************************************************************
Models and parameters used in the CCONE calculation
1) Optical model
* coupled channels calculation
coupled levels: 0,1,2,3,11 (see Table 1)
* optical model potential
neutron omp: Kunieda,S. et al./9/ (+)
proton omp: Koning,A.J. and Delaroche,J.P./10/
deuteron omp: Lohr,J.M. and Haeberli,W./11/
triton omp: Becchetti Jr.,F.D. and Greenlees,G.W./12/
He3 omp: Becchetti Jr.,F.D. and Greenlees,G.W./12/
alpha omp: Huizenga,J.R. and Igo,G./13/
(+) omp parameters were modified.
2) Two-component exciton model/14/
* Global parametrization of Koning-Duijvestijn/15/
was used.
* Gamma emission channel/16/ was added to simulate direct
and semi-direct capture reaction.
3) Hauser-Feshbach statistical model
* Width fluctuation correction/17/ 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/18/.
Parameters are shown in Table 2.
* Gamma-ray strength function of enhanced generalized
Lorentzian form/19/,/20/ 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 W-184
-------------------
No. Ex(MeV) J PI
-------------------
0 0.00000 0 + *
1 0.11121 2 + *
2 0.36406 4 + *
3 0.74831 6 + *
4 0.90328 2 +
5 1.00248 0 +
6 1.00597 3 +
7 1.12144 2 +
8 1.13003 2 -
9 1.13384 4 +
10 1.22129 3 -
11 1.25230 8 + *
12 1.28360 2 -
13 1.28499 5 -
14 1.29492 5 +
15 1.32213 0 +
16 1.34538 4 -
17 1.36037 4 +
18 1.38631 2 +
19 1.42499 3 +
20 1.43100 2 +
21 1.44626 6 -
22 1.47700 6 +
23 1.49200 5 -
24 1.50154 7 -
25 1.52328 3 +
26 1.53686 4 +
27 1.57024 2 +
28 1.58145 6 -
29 1.61356 1 +
30 1.61487 1 +
-------------------
*) Coupled levels in CC calculation
Table 2. Level density parameters
--------------------------------------------------------
Nuclide a* Pair Eshell T E0 Ematch
1/MeV MeV MeV MeV MeV MeV
--------------------------------------------------------
W-185 22.7200 0.8823 1.2247 0.4842 -0.8101 4.9225
W-184 22.1100 1.7693 1.2350 0.5106 -0.1439 6.1796
W-183 21.5000 0.8871 1.1150 0.5015 -0.7444 4.9247
W-182 21.6000 1.7790 1.2320 0.4968 0.1520 5.7824
Ta-184 21.4138 0.0000 1.3866 0.3893 -0.5346 2.1728
Ta-183 20.6300 0.8871 1.5183 0.4673 -0.2784 4.1815
Ta-182 20.4000 0.0000 1.1768 0.4917 -1.3065 3.5848
Ta-181 22.2900 0.8920 1.4278 0.4666 -0.5553 4.5420
Hf-183 22.0008 0.8871 1.6503 0.4912 -0.8609 4.9869
Hf-182 21.3733 1.7790 1.7280 0.5008 0.0219 5.9188
Hf-181 22.0100 0.8920 1.4311 0.4845 -0.7193 4.8126
Hf-180 20.9400 1.7889 1.5810 0.5569 -0.5865 6.8900
Hf-179 21.3300 0.8969 1.6163 0.4997 -0.8128 4.9790
Hf-178 21.4500 1.7989 1.8369 0.5406 -0.5584 6.7847
--------------------------------------------------------
Table 3. Gamma-ray strength function for W-185
--------------------------------------------------------
K0 = 1.140 E0 = 4.500 (MeV)
* E1: ER = 12.59 (MeV) EG = 2.29 (MeV) SIG = 211.00 (mb)
ER = 14.88 (MeV) EG = 5.18 (MeV) SIG = 334.00 (mb)
ER = 5.30 (MeV) EG = 1.80 (MeV) SIG = 2.50 (mb)
* M1: ER = 7.20 (MeV) EG = 4.00 (MeV) SIG = 1.03 (mb)
* E2: ER = 11.06 (MeV) EG = 3.89 (MeV) SIG = 4.53 (mb)
--------------------------------------------------------
References
1) Camarda H.S. et al.: Phys. Rev. C8, 1813 (1973).
2) Ohkubo M.: JAERI-M 5624 (1974).
3) Macklin R.L. et al.: LA-9200-MS (1982).
4) Mughabghab S.F.:"Neutron Cross Sections", Vol. 1, part B
(1984).
5) Mughabghab,S.F.: "Atlas of Neutron Resonances, Fifth
Edition: Resonance Parameters and Thermal Cross Sections.
Z=1-100", Elsevier Science (2006).
6) Kikuchi,Y. et al.: JAERI-Data/Code 99-025 (1999)
[in Japanese].
7) Iwamoto,O.: JAERI-Data/Code 2003-020 (2003).
8) Iwamoto,O.: J. Nucl. Sci. Technol., 44, 687 (2007).
9) Kunieda,S. et al.: J. Nucl. Sci. Technol. 44, 838 (2007).
10) Koning,A.J. and Delaroche,J.P.: Nucl. Phys. A713, 231 (2003)
[Global potential].
11) Lohr,J.M. and Haeberli,W.: Nucl. Phys. A232, 381 (1974).
12) Becchetti Jr.,F.D. and Greenlees,G.W.: Ann. Rept.
J.H.Williams Lab., Univ. Minnesota (1969).
13) Huizenga,J.R. and Igo,G.: Nucl. Phys. 29, 462 (1962).
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(1994).
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20) Kopecky,J., Uhl,M., Chrien,R.E.: Phys. Rev. C47, 312 (1990).