54-Xe-128

 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.