96-Cm-247

 96-Cm-247 JAEA+      EVAL-FEB10 O.Iwamoto, T.Nakagawa, et al.    
                      DIST-MAY10                       20100318   
----JENDL-4.0         MATERIAL 9646                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
History                                                           
05-06 Fission cross section was evaluated with GMA.               
06-05 Resonance parameters were modified.                         
06-12 GMA results were revised.                                   
07-05 New calculation was made with CCONE code.                   
08-03 Recalculation with CCONE code was performed.                
      Data were compiled as JENDL/AC-2008/1/.                     
10-02 Data of prompt gamma rays due to fission were given.        
10-03 Covariance data were given.                                 
                                                                  
                                                                  
MF= 1 General information                                         
  MT=452 Number of Neutrons per fission                           
    Sum of MT's=455 and 456.                                      
                                                                  
  MT=455 Delayed neutron data                                     
    (same as JENDL-3.3)                                           
    Semi-empirical formula by Tuttle/2/.                          
                                                                  
  MT=456 Number of prompt neutrons per fission                    
    (same as JENDL-3.3)                                           
    At the 0 eV, the experimental data of Zhuravlev et al./3/     
    was adopted. An energy-dependent term was based on the semi-  
    empirical formula by Howerton/4/.                             
                                                                  
                                                                  
MF= 2 Resonance parameters                                        
  MT=151                                                          
  Resolved resonance parameters (MLBW: 1.0E-5 - 60 eV)            
    Resonance parameters of Moore and Keyworth/5/ and Danon       
    et al./6/ were adopted. Resonance energies of Ref./5/ were    
    shifted down by 0.3%. The parameters were adjusted to the     
    measured fission cross sections/5,6/.                         
                                                                  
    The thermal cross sections to be reproduced:                  
      Fission = 94.6 +- 3.1 b                                     
         Danon et al./6/, Diamond et al./7/, Benjamin et al./8/,  
         Zhuravlev et al./9/, etc.                                
      Capture = 60 +- 10 b                                        
         Gavrilov et al./10/                                      
                                                                  
  Unresolved resonance parameters (60 eV - 40 keV)                
    Parameters were determined with ASREP code/11/ so as to       
    reproduce the cross sections. They are used only for self-    
    shielding calculations.                                       
                                                                  
     Thermal cross sections and resonance integrals (at 300K)     
    -------------------------------------------------------       
                    0.0253 eV    reson. integ.(*)                 
                     (barns)       (barns)                        
    -------------------------------------------------------       
    total           163.023                                       
    elastic           8.348                                       
    fission          94.744          945                          
    capture          59.931          503                          
    -------------------------------------------------------       
         (*) In the energy range from 0.5 eV to 10 MeV.           
                                                                  
                                                                  
MF= 3 Neutron cross sections                                      
  Cross sections above the resolved resonance region except for   
  the elastic scattering (MT=2) and fission cross sections (MT=18,
  19, 20, 21, 38) were calculated with CCONE code/12/.            
                                                                  
  MT= 1 Total cross section                                       
    The cross section was calculated with CC OMP of Soukhovitskii 
    et al./13/                                                    
                                                                  
  MT= 2 Elastic scattering cross section                          
    Calculated as total - non-elastic scattering cross sections.  
                                                                  
  MT=18 Fission cross section (Above 115 eV)                      
    The following experimental data were analyzed in the energy   
    range from 115 eV to 20 MeV with the GMA code /14/:           
                                                                  
       Authors        Energy range     Data points  Reference     
       Moore+         50eV - 1.9MeV        3523      /5/          
       Fomushkin+     20keV - 3MeV           27      /15/         
       Fomushkin+     14 MeV                  1      /16/         
       Danon+         500eV - 98keV          45      /17/         
       Danon+         0.01eV - 9.8keV      1018      /6/          
       Ivanin+        130keV - 8.3MeV        81      /18/         
       Fursov+        135keV - 15MeV         68      /19/(*1)     
                                                                  
    (*1) Ratio to Pu-239 fission. JENDL-3.3 data were used to     
         convert them to cross sections.                          
                                                                  
    The results of GMA were used to determine the parameters in   
    the CCONE calculation.                                        
                                                                  
    In the energy regions from 40 to 500keV and above 6 MeV,      
    eye-guided curves were adopted.                               
                                                                  
  MT=19, 20, 21, 38 Multi-chance fission cross sections           
    Calculated with CCONE code, and renormalized to the total     
    fission cross section (MT=18).                                
                                                                  
                                                                  
MF= 4 Angular distributions of secondary neutrons                 
  MT=2 Elastic scattering                                         
    Calculated with CCONE code.                                   
                                                                  
  MT=18 Fission                                                   
    Isotropic distributions in the laboratory system were assumed.
                                                                  
                                                                  
MF= 5 Energy distributions of secondary neutrons                  
  MT=18 Prompt neutron spectra                                    
    Calculated with CCONE code/12/.                               
                                                                  
                                                                  
MF= 6 Energy-angle distributions                                  
    Calculated with CCONE code.                                   
    Distributions from fission (MT=18) are not included.          
                                                                  
                                                                  
MF=12 Photon production multiplicities                            
  MT=18 Fission                                                   
    Calculated from the total energy released by the prompt       
    gamma-rays due to fission which was estimated from its        
    systematics, and the average energy of gamma-rays.            
                                                                  
                                                                  
MF=14 Photon angular distributions                                
  MT=18 Fission                                                   
    Isotoropic distributions were assumed.                        
                                                                  
                                                                  
MF=15 Continuous photon energy spectra                            
  MT=18 Fission                                                   
    Experimental data measured by Verbinski et al./20/ for        
    Pu-239 thermal fission were adopted.                          
                                                                  
                                                                  
MF=31 Covariances of average number of neutrons per fission       
  MT=452 Number of neutrons per fission                           
    Sum of covariances for MT=455 and MT=456.                     
                                                                  
  MT=455                                                          
    Error of 15% was assumed.                                     
                                                                  
  MT=456                                                          
    Covariance was obtained by fitting a linear function to the   
    data at 0.0 and 5.0 MeV with an uncertainty of 4% and 5%,     
    respevtively. The uncertainty at 0 eV was estimated from the  
    experimental data of Zhuravlev et al./3/                      
                                                                  
                                                                  
MF=32 Covariances of resonance parameters                         
  MT=151 Resolved resonance parameterss                           
    Format of LCOMP=0 was adopted.                                
                                                                  
    Uncertainties of parameters were taken from Mughabghab /21/.  
    For the parameters without any information on uncertainty,    
    the following uncertainties were assumed:                     
       Resonance energy    0.1 %                                  
       Neutron width       10 %                                   
       Capture width       30 %                                   
       Fission width       20 %                                   
                                                                  
    They were further modified by considering experimental data   
    of the fission cross section at the thermal neutron energy.   
                                                                  
                                                                  
MF=33 Covariances of neutron cross sections                       
  Covariances were given to all the cross sections by using       
  KALMAN code/22/ and the covariances of model parameters         
  used in the cross-section calculations.                         
                                                                  
  For the fission cross section, covariances obtained with the    
  GMA analysis were adopted. Standard deviations of about 10%     
  were assumed in the energy region above 8 MeV.                  
                                                                  
  In the resolved resonance region, the following standard        
  deviations were added to the contributions from resonance       
  parameters:                                                     
       Total               10 %                                   
       Elastic scattering  20 %                                   
       Capture             20 %                                   
                                                                  
                                                                  
MF=34 Covariances for Angular Distributions                       
  MT=2 Elastic scattering                                         
    Covariances were given only to P1 components.                 
                                                                  
                                                                  
MF=35 Covariances for Energy Distributions                        
  MT=18 Fission spectra                                           
    Estimated with CCONE and KALMAN codes.                        
                                                                  
                                                                  
***************************************************************** 
  Calculation with CCONE code                                     
***************************************************************** 
                                                                  
  Models and parameters used in the CCONE/12/ calculation         
  1) Coupled channel optical model                                
     Levels in the rotational band were included. Optical model   
     potential and coupled levels are shown in Table 1.           
                                                                  
  2) Two-component exciton model/23/                              
    * Global parametrization of Koning-Duijvestijn/24/            
      was used.                                                   
    * Gamma emission channel/25/ was added to simulate direct     
      and semi-direct capture reaction.                           
                                                                  
  3) Hauser-Feshbach statistical model                            
    * Moldauer width fluctuation correction/26/ was included.     
    * Neutron, gamma and fission decay channel were included.     
    * Transmission coefficients of neutrons were taken from       
      coupled channel calculation in Table 1.                     
    * The level scheme of the target is shown in Table 2.         
    * Level density formula of constant temperature and Fermi-gas 
      model were used with shell energy correction and collective 
      enhancement factor. Parameters are shown in Table 3.        
    * Fission channel:                                            
      Double humped fission barriers were assumed.                
      Fission barrier penetrabilities were calculated with        
      Hill-Wheler formula/27/. Fission barrier parameters were    
      shown in Table 4. Transition state model was used and       
      continuum levels are assumed above the saddles. The level   
      density parameters for inner and outer saddles are shown in 
      Tables 5 and 6, respectively.                               
    * Gamma-ray strength function of Kopecky et al/28/,/29/       
      was used. The prameters are shown in Table 7.               
                                                                  
                                                                  
------------------------------------------------------------------
                              Tables                              
------------------------------------------------------------------
                                                                  
Table 1. Coupled channel calculation                              
  --------------------------------------------------              
  * rigid rotor model was applied                                 
  * coupled levels = 0,1,2,3,33 (see Table 2)                     
  * optical potential parameters /13/                             
    Volume:                                                       
      V_0       = 49.97    MeV                                    
      lambda_HF = 0.01004  1/MeV                                  
      C_viso    = 15.9     MeV                                    
      A_v       = 12.04    MeV                                    
      B_v       = 81.36    MeV                                    
      E_a       = 385      MeV                                    
      r_v       = 1.2568   fm                                     
      a_v       = 0.633    fm                                     
    Surface:                                                      
      W_0       = 17.2     MeV                                    
      B_s       = 11.19    MeV                                    
      C_s       = 0.01361  1/MeV                                  
      C_wiso    = 23.5     MeV                                    
      r_s       = 1.1803   fm                                     
      a_s       = 0.601    fm                                     
    Spin-orbit:                                                   
      V_so      = 5.75     MeV                                    
      lambda_so = 0.005    1/MeV                                  
      W_so      = -3.1     MeV                                    
      B_so      = 160      MeV                                    
      r_so      = 1.1214   fm                                     
      a_so      = 0.59     fm                                     
    Coulomb:                                                      
      C_coul    = 1.3                                             
      r_c       = 1.2452   fm                                     
      a_c       = 0.545    fm                                     
    Deformation:                                                  
      beta_2    = 0.213                                           
      beta_4    = 0.066                                           
      beta_6    = 0.0015                                          
                                                                  
  * Calculated strength function                                  
    S0= 1.18e-4 S1= 2.99e-4 R'=  9.09 fm (En=1 keV)               
  --------------------------------------------------              
                                                                  
Table 2. Level Scheme of Cm-247                                   
  -------------------                                             
  No.  Ex(MeV)   J PI                                             
  -------------------                                             
   0  0.00000  9/2 -  *                                           
   1  0.06167 11/2 -  *                                           
   2  0.13465 13/2 -  *                                           
   3  0.21900 15/2 -  *                                           
   4  0.22738  5/2 +                                              
   5  0.26586  7/2 +                                              
   6  0.28541  7/2 +                                              
   7  0.30900  9/2 -                                              
   8  0.31830  9/2 +                                              
   9  0.33600  7/2 +                                              
  10  0.34590  9/2 +                                              
  11  0.37000 13/2 -                                              
  12  0.38100 11/2 +                                              
  13  0.39800 11/2 +                                              
  14  0.40490  1/2 +                                              
  15  0.41700  9/2 +                                              
  16  0.43300  3/2 +                                              
  17  0.43900 13/2 +                                              
  18  0.44800  5/2 +                                              
  19  0.50600  1/2 +                                              
  20  0.51670  7/2 +                                              
  21  0.51858  3/2 +                                              
  22  0.55000  9/2 +                                              
  23  0.58170  5/2 +                                              
  24  0.59200  9/2 +                                              
  25  0.60400  7/2 +                                              
  -------------------                                             
  *) Coupled levels in CC calculation                             
                                                                  
Table 3. Level density parameters                                 
  --------------------------------------------------------        
  Nuclide      a*    Pair  Eshell       T      E0  Ematch         
            1/MeV     MeV     MeV     MeV     MeV     MeV         
  --------------------------------------------------------        
   Cm-248 18.5357  1.5240  2.0504  0.3482  0.2818  3.2555         
   Cm-247 18.3955  0.7635  1.7794  0.3734 -0.6804  2.7533         
   Cm-246 18.8984  1.5302  1.7310  0.3608  0.1621  3.4286         
   Cm-245 18.8322  0.7667  1.4601  0.3623 -0.5771  2.6382         
   Cm-244 19.1414  1.5364  1.5347  0.3530  0.2436  3.3454         
  --------------------------------------------------------        
                                                                  
Table 4. Fission barrier parameters                               
  ----------------------------------------                        
  Nuclide     V_A    hw_A     V_B    hw_B                         
              MeV     MeV     MeV     MeV                         
  ----------------------------------------                        
   Cm-248   6.100   1.040   4.950   0.600                         
   Cm-247   5.400   0.800   5.650   0.650                         
   Cm-246   6.300   1.040   5.100   0.600                         
   Cm-245   6.050   0.500   5.700   0.420                         
   Cm-244   6.100   0.900   5.100   0.600                         
  ----------------------------------------                        
                                                                  
Table 5. Level density above inner saddle                         
  --------------------------------------------------------        
  Nuclide      a*    Pair  Eshell       T      E0  Ematch         
            1/MeV     MeV     MeV     MeV     MeV     MeV         
  --------------------------------------------------------        
   Cm-248 20.9336  1.5000  2.6000  0.3323 -1.0300  3.6000         
   Cm-247 20.8609  0.8908  2.6000  0.3256 -1.5320  2.8908         
   Cm-246 20.7882  1.6500  2.6000  0.3263 -0.7728  3.6500         
   Cm-245 20.7155  0.8944  2.6000  0.3342 -1.6357  2.9944         
   Cm-244 20.6427  1.7925  2.6000  0.3275 -0.6303  3.7925         
  --------------------------------------------------------        
                                                                  
Table 6. Level density above outer saddle                         
  --------------------------------------------------------        
  Nuclide      a*    Pair  Eshell       T      E0  Ematch         
            1/MeV     MeV     MeV     MeV     MeV     MeV         
  --------------------------------------------------------        
   Cm-248 20.9336  1.7780  0.8600  0.3706 -0.1043  3.9780         
   Cm-247 20.8609  0.8908  0.8200  0.3573 -0.8210  2.8908         
   Cm-246 20.7882  1.7852  0.7800  0.3658 -0.0107  3.8852         
   Cm-245 20.7155  0.8944  0.7400  0.3596 -0.8163  2.8944         
   Cm-244 20.6427  1.7925  0.7000  0.3455  0.2502  3.5925         
  --------------------------------------------------------        
                                                                  
Table 7. Gamma-ray strength function for Cm-248                   
  --------------------------------------------------------        
  * E1: ER = 11.40 (MeV) EG = 2.71 (MeV) SIG = 331.48 (mb)        
        ER = 14.30 (MeV) EG = 4.18 (MeV) SIG = 429.81 (mb)        
  * M1: ER =  6.53 (MeV) EG = 4.00 (MeV) SIG =   1.48 (mb)        
  * E2: ER = 10.03 (MeV) EG = 3.13 (MeV) SIG =   7.06 (mb)        
  --------------------------------------------------------        
                                                                  
                                                                  
References                                                        
 1) O.Iwamoto et al.: J. Nucl. Sci. Technol., 46, 510 (2009).     
 2) R.J.Tuttle: INDC(NDS)-107/G+Special, p.29 (1979).             
 3) K.D.Zhuravlev et al.: 1973 Kiev, vol. 4, p.57 (1973).         
 4) R.J.Howerton: Nucl. Sci. Eng., 62, 438 (1977).                
 5) M.S.Moore, G.A.Keyworth: Phys. Rev., C3, 1656 (1971).         
 6) Y.Danon et al.: 1994 Gatlinburg, Vol.1, p.245 (1994).         
 7) H.Diamond et al.: J. Inorg. Nucl., 30, 2553 (1968).           
 8) R.W.Benjamin et al.: Nucl. Sci. Eng., 47, 203 (1972).         
 9) K.D.Zhuravlev et al.: Sov. At. Energy, 39, 907 (1976).        
10) V.D.Gavrilov, V.A.Goncharov: Sov. At. Energy, 44, 274         
    (1978).                                                       
11) Y.Kikuchi et al.: JAERI-Data/Code 99-025 (1999) in Japanese.  
12) O.Iwamoto: J. Nucl. Sci. Technol., 44, 687 (2007).            
13) E.Sh.Soukhovitskii et al.: Phys. Rev. C72, 024604 (2005).     
14) W.P.Poenitz: BNL-NCS-51363, Vol.I, p.249 (1981).              
    S.Chiba, D.L.Smith: ANL/NDM-121 (1991).                       
15) E.F.Fomushkin et al.: Sov. At. Energy, 62, 340 (1987).        
16) E.F.Fomushkin et al.: 1991 Juelich, p.439 (1991).             
17) Y.Danon et al.: Nucl. Sci. Eng., 109, 341 (1991).             
18) I.A.Ivanin et al.: 1997 Trieste, Vol.1, p.664 (1997).         
19) B.I.Fursov et al.: 1997 Trieste, Vol.1, p.488 (1997).         
20) V.V.Verbinski et al.: Phys. Rev., C7, 1173 (1973).            
21) S.F.Mughabghab: "Atlas of Neutron Resonances," Elsevier       
   (2006).                                                        
22) T.Kawano, K.Shibata, JAERI-Data/Code 97-037 (1997) in         
    Japanese.                                                     
23) C.Kalbach: Phys. Rev. C33, 818 (1986).                        
24) A.J.Koning, M.C.Duijvestijn: Nucl. Phys. A744, 15 (2004).     
25) J.M.Akkermans, H.Gruppelaar: Phys. Lett. 157B, 95 (1985).     
26) P.A.Moldauer: Nucl. Phys. A344, 185 (1980).                   
27) D.L.Hill, J.A.Wheeler: Phys. Rev. 89, 1102 (1953).            
28) J.Kopecky, M.Uhl: Phys. Rev. C41, 1941 (1990).                
29) J.Kopecky, M.Uhl, R.E.Chrien: Phys. Rev. C47, 312 (1990).