64-Gd-154

 64-Gd-154 JAEA+      EVAL-Dec09 N.Iwamoto,A.Zukeran,K.Shibata    
                      DIST-MAY10                       20100119   
----JENDL-4.0         MATERIAL 6431                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
History                                                           
09-12 The resolved resonance parameters were evaluated by         
      A.Zukeran,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 2.76 keV     
      Resonance parameters below 486 eV were evaluated on the     
      basis of Mughabghab/1/.  Above 486 eV, parameters were      
      adopted from Macklin/2/.  For the resonances only whose     
      capture area was measured, neutron widths were determined   
      from the capture area and an average radiation width of     
      0.088 eV/1/.  The total spin J and orbital angular          
      momentum L were assigned by considering the magnitude       
      of the capture area of each resonance.  A negative resonance
      was added so as to reproduce the thermal capture cross      
      section of 85+-12 barns/1/.  Scattering radius of 8.0 fm    
      was estimated from an optical model calculation shown in    
      fig. 2 of ref./1/.                                          
      In JENDL-4, the data for 11.57 - 269.6 eV were replaced with
      the ones obtained by Leinweber et al./3/  The energy of     
      the negative resonance was adjusted.                        
                                                                  
    Unresolved resonance region : 2.76 keV - 300.0 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   
      CCOM /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           9.1626e+01                                 
       Elastic         6.5644e+00                                 
       n,gamma         8.5061e+01           2.8797e+02            
       n,alpha         1.5070e-06                                 
      ----------------------------------------------------------  
         (*) 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= 24 (n,2na) cross section                                    
    Calculated with CCONE code /6/.                               
                                                                  
  MT= 28 (n,np) cross section                                     
    Calculated with CCONE code /6/.                               
                                                                  
  MT= 32 (n,nd) 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= 24 (n,2na) reaction                                         
    Calculated with CCONE code /6/.                               
                                                                  
  MT= 28 (n,np) reaction                                          
    Calculated with CCONE code /6/.                               
                                                                  
  MT= 32 (n,nd) 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: 0,1,2,4,10 (see Table 1)                    
                                                                  
    * optical model potential                                     
      neutron  omp: Kunieda,S. et al./7/ (+)                      
      proton   omp: Koning,A.J. and Delaroche,J.P./8/             
      deuteron omp: Lohr,J.M. and Haeberli,W./9/                  
      triton   omp: Becchetti Jr.,F.D. and Greenlees,G.W./10/     
      He3      omp: Becchetti Jr.,F.D. and Greenlees,G.W./10/     
      alpha    omp: Huizenga,J.R. and Igo,G./11/                  
      (+) omp parameters were modified.                           
                                                                  
  2) Two-component exciton model/12/                              
    * Global parametrization of Koning-Duijvestijn/13/            
      was used.                                                   
    * Gamma emission channel/14/ was added to simulate direct     
      and semi-direct capture reaction.                           
                                                                  
  3) Hauser-Feshbach statistical model                            
    * Width fluctuation correction/15/ 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/16/.           
      Parameters are shown in Table 2.                            
    * Gamma-ray strength function of enhanced generalized         
      Lorentzian form/17/,/18/ 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 Gd-154                                   
  -------------------                                             
  No.  Ex(MeV)  J  PI                                             
  -------------------                                             
   0  0.00000   0  +  *                                           
   1  0.12307   2  +  *                                           
   2  0.37100   4  +  *                                           
   3  0.68066   0  +                                              
   4  0.71766   6  +  *                                           
   5  0.81548   2  +                                              
   6  0.99625   2  +                                              
   7  1.04758   4  +                                              
   8  1.12778   3  +                                              
   9  1.13596   2  +                                              
  10  1.14443   8  +  *                                           
  11  1.18208   0  +                                              
  12  1.23310   3  -                                              
  13  1.24127   1  -                                              
  14  1.25162   3  -                                              
  15  1.26378   4  +                                              
  16  1.27699   4  +                                              
  17  1.29417   2  +                                              
  18  1.29547   0  +                                              
  19  1.36500   1  +                                              
  20  1.36587   6  +                                              
  21  1.39752   2  -                                              
  22  1.40407   5  -                                              
  23  1.41442   1  -                                              
  24  1.41814   2  +                                              
  25  1.43258   5  +                                              
  -------------------                                             
  *) Coupled levels in CC calculation                             
                                                                  
Table 2. Level density parameters                                 
  --------------------------------------------------------        
  Nuclide      a*    Pair  Eshell       T      E0  Ematch         
            1/MeV     MeV     MeV     MeV     MeV     MeV         
  --------------------------------------------------------        
   Gd-155 20.5000  0.9639  3.7045  0.5229 -1.4800  5.7609         
   Gd-154 18.5215  1.9340  3.6018  0.5706 -0.6048  7.0075         
   Gd-153 20.9000  0.9701  3.9793  0.5231 -1.6694  5.9506         
   Gd-152 18.3157  1.9467  3.2774  0.5203  0.2124  5.9623         
   Eu-154 19.2000  0.0000  3.6717  0.5485 -2.4486  4.8922         
   Eu-153 17.3400  0.9701  3.8805  0.5963 -1.6297  6.1695         
   Eu-152 19.7700  0.0000  4.2144  0.5244 -2.4180  4.7265         
   Eu-151 21.0000  0.9765  3.8814  0.4854 -1.1094  5.2279         
   Sm-153 20.0000  0.9701  3.6781  0.5579 -1.8633  6.3072         
   Sm-152 19.7000  1.9467  3.6242  0.5066 -0.0488  6.1904         
   Sm-151 20.8000  0.9765  3.9732  0.5224 -1.6295  5.9141         
   Sm-150 19.2000  1.9596  3.2458  0.5078  0.1619  6.0033         
   Sm-149 19.2000  0.9831  2.9030  0.5042 -0.6887  4.8887         
   Sm-148 18.4000  1.9728  2.0339  0.5337  0.3686  5.9610         
  --------------------------------------------------------        
                                                                  
Table 3. Gamma-ray strength function for Gd-155                   
  --------------------------------------------------------        
  K0 = 2.000   E0 = 4.500 (MeV)                                   
  * E1: ER = 11.20 (MeV) EG = 2.60 (MeV) SIG = 180.00 (mb)        
        ER = 15.20 (MeV) EG = 3.60 (MeV) SIG = 242.00 (mb)        
  * M1: ER =  7.63 (MeV) EG = 4.00 (MeV) SIG =   1.82 (mb)        
  * E2: ER = 11.73 (MeV) EG = 4.25 (MeV) SIG =   3.70 (mb)        
  --------------------------------------------------------        
                                                                  
References                                                        
 1) Mughabghab, S.F.: "Neutron Cross Sections, Vol. I, Part B",   
    Academic Press (1984).                                        
 2) Macklin, R.L.: Nucl. Sci. Eng., 95. 304 (1987).               
 3) Leinweber, G et al.: Nucl. Sci. Eng., 154, 261 (2006).        
 4) Kikuchi,Y. et al.: JAERI-Data/Code 99-025 (1999)              
    [in Japanese].                                                
 5) Iwamoto,O.: JAERI-Data/Code 2003-020 (2003).                  
 6) Iwamoto,O.: J. Nucl. Sci. Technol., 44, 687 (2007).           
 7) Kunieda,S. et al.: J. Nucl. Sci. Technol. 44, 838 (2007).     
 8) Koning,A.J. and Delaroche,J.P.: Nucl. Phys. A713, 231 (2003)  
    [Global potential].                                           
 9) Lohr,J.M. and Haeberli,W.: Nucl. Phys. A232, 381 (1974).      
10) Becchetti Jr.,F.D. and Greenlees,G.W.: Ann. Rept.             
    J.H.Williams Lab., Univ. Minnesota (1969).                    
11) Huizenga,J.R. and Igo,G.: Nucl. Phys. 29, 462 (1962).         
12) Kalbach,C.: Phys. Rev. C33, 818 (1986).                       
13) Koning,A.J., Duijvestijn,M.C.: Nucl. Phys. A744, 15 (2004).   
14) Akkermans,J.M., Gruppelaar,H.: Phys. Lett. 157B, 95 (1985).   
15) Moldauer,P.A.: Nucl. Phys. A344, 185 (1980).                  
16) Mengoni,A. and Nakajima,Y.: J. Nucl. Sci. Technol., 31, 151   
    (1994).                                                       
17) Kopecky,J., Uhl,M.: Phys. Rev. C41, 1941 (1990).              
18) Kopecky,J., Uhl,M., Chrien,R.E.: Phys. Rev. C47, 312 (1990).