74-W -182

 74-W -182 KHI,NEDAC  EVAL-MAR87 T.WATANABE(KHI), T.ASAMI(NEDAC)  
                      DIST-MAR02 REV3-NOV01            20011121   
----JENDL-3.3         MATERIAL 7431                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
HISTORY                                                           
87-03  New evaluation was made for JENDL-3.                       
87-03  Compiled by T.Asami.                                       
94-01  JENDL-3.2.                                                 
       Compiled by T.Nakagawa (ndc/jaeri)                         
00-03  Reevaluation was made by T.Asami.                          
01-11  Compiled by K.Shibata (ndc/jaeri)                          
                                                                  
    *****   modified parts for JENDL-3.3 from JENDL-3.2   *****   
     (3,2)                re-calculated                           
     (3,203,207)          added                                   
     (3,251)              deleted                                 
     (4,2)                transformation matrix deleted           
     (4,16,17,22,28,91)   deleted                                 
     (5,16,17,22,28,91)   deleted                                 
     (6,16,17,22,28,91)   taken from JENDL fusion file            
     (6,203,204,207)      taken from JENDL fusion file            
     (12,22-107)          evaluated newly                         
     (13,3)               evaluated newly                         
     (14,3-107)           isotropic distributioins                
     (15,3-107)           evaluated newly                         
    ***********************************************************   
                                                                  
    The JENDL fusion file /1/ and the modification of JENDL-3.2   
      from JENDL-3.1 as follows:                                  
                                                                  
     -------------------------------------------------------------
      JENDL fusion file /1/  (as of Jan. 1994)                    
            Evaluated by K.Kosako (nedac) and S. Chiba (ndc/jaeri)
            Compiled  by K.Kosako.                                
                                                                  
      Data were taken from JENDL-3.1 except for the following:    
      -  The inelastic scattering cross sections to the levels    
         above mt=59 and angular distributions of inelastically   
         scattered neutrons (except continuum inelastic) were     
         calculated with casthy2y and dwucky in sincros-ii        
         system/2/ including contributions from direct reactions. 
      -  The (n,2n), (n,3n), (n,na), (n,np), (n,p), (n,d) and     
         (n,a) reaction cross sections (mt=16, 17, 22, 28, 103,   
         104, 107) were calculated by egnash2 in the sincros-ii.  
      -  Energy distributions of secondary neutrons were replaced 
         by those calculated by egnash2.  The ddx's of the        
         continuum neutrons were calculated by Kumabe's systema-  
         tics /3/ using f15tob /1/.  The precompound/compound     
         ratio was calculated by the sincros- ii code system.     
      -  Optical-model, level density and other parameters used in
         the sincros-ii calculation are described in ref./2/.     
         level schemes were determined on the basis of ENSDF/4/.  
                                                                  
   For JENDL-3.2 and JENDL fusion file, all cross section data    
   except for the total, elastic scattering, capture and          
   some of the inelstic scattering cross sections were            
   calculated with sincros-ii system/2/ by adopting               
   Walter-Guss omp modified by Yamamuro/2/ for neutron,           
   Perey omp /12/ for proton, Lemos omp modified by Arthur and    
   Young/13/ for alpha, Lohr-Haeberli omp/14/ for deuteron,       
   Becchettii-Greenlees omp/15/ for triton and he-3, and standard 
   level density parameters of sincros-ii system.                 
     -------------------------------------------------------------
                                                                  
                                                                  
                                                                  
mf=1  General information                                         
 mt=451  Descriptive data and dictionary                          
                                                                  
mf=2  Resonance parameters                                        
 mt=151  Resolved resonance parameters                            
   Resolved parameters for mlbw formula were given in the energy  
   region from 1.0e-5 eV to 12 keV.                               
      Parameters were evaluated in examining both the experimental
   data/5,6,7/ and the recommended data in ref./8/.  For unknown  
   radiative width, an average value of 53 milli-eV was assumed.  
   Parameters for a negative resonance were selected so that the  
   2200 m/s cross sections agreed with a recommended capture cross
   section of 20.7 barns/8/ and the experimental data for total   
   cross sections around thermal energies.  The scattering radius 
   was assumed to be 7.5 fermi.                                   
                                                                  
   calculated 2200 m/sec cross sections and resonance integrals   
   are as follows:                                                
           2200 m/s cross section(b)     res. integral(b)         
   elastic        8.84                                            
   capture       20.7                       628.                  
   total         29.6                                             
                                                                  
mf=3  Neutron cross sections                                      
   Below 12 keV, zero background cross section was given and  all 
   the cross-section data are reproduced from the evaluated       
   resolved resonance parameters.                                 
                                                                  
   For JENDL-3.1, above 12 keV, the total and partial cross       
   sections were given mainly based on the theoretical calcula-   
   tions. The total, elastic and inelastic scattering, and capture
   cross sections were calculated with the coupled-channel model  
   and the spherical optical-statistical model.  Tthe calculations
   were performed with a combined program of casthy/9/ and        
   ecis/10/.  The optical potential parameters used are:          
         V = 48.83 - 0.0809*En,    Vso = 5.6    (MeV)             
        Ws = 6.73 - 0.0536*En,      Wv = 0      (MeV)             
         r = 1.168, rs = 1.268, rso = 1.592     (fm)              
         a = 0.617, aso = 0.664, b = 0.563      (fm)              
   The deformed potential parameters were taken from the work of  
   Delaroche/11/.                                                 
                                                                  
                                                                  
 mt=1 Total                                                       
   Below 12 keV,  reproduced from the evaluated resolved resona-  
   nce parameters.                                                
   Above 12 keV, calculated with the combined program of the ecis 
   and casthy codes. almost the same as JENDL-3.1.                
                                                                  
 mt=2 Elastic scattering                                          
   Obtained by subtracting the sum of the partial cross sections  
   from the total cross section.                                  
                                                                  
 mt=4, 51-70, 91 Inelastic scattering                             
   The data of mt=51 to 58 were calculated with the combined      
   program of ecis/10/ and casthy /9/.  These cross sections      
   are the same as JENDL-3.1 except that new calculation          
   was made at several energy points.  The other cross sections   
   were calculated with sincros-ii for JENDL fusion file.  The    
   level scheme was based on ref./4/ contributions of the direct  
   process was calculated for the levels marked with '*'.         
                                                                  
       no.  mt   energy(MeV)     spin-parity (direct process)     
      g.s.        0.0                 0+                          
       1    51    0.1001              2+         *                
       2    52    0.3294              4+         *                
       3    53    0.6805              6+         *                
       4    54    1.1358              0+                          
       5    55    1.1444              8+         *                
       6    56    1.2214              2+                          
       7    56    1.2574              2+                          
       8    56    1.2892              2-                          
       9    57    1.3311              3+                          
      10    57    1.3738              3-                          
      11    58    1.4428              4+                          
      12    58    1.4875              4-                          
      13    58    1.5102              4+                          
      14    58    1.5532              4-                          
      15    58    1.6213              5-                          
      16    58    1.6235              5+                          
      17    58    1.6604              5-                          
      18    59    1.7119             10+         *                
      19    60    1.7568              6+                          
      20    61    1.7654              4+                          
      21    62    1.7690              5-                          
      22    63    1.8097              5-                          
      23    64    1.8109              6-                          
      24    65    1.8134              4-                          
      25    66    1.8295              6-                          
      26    67    1.8331              2-                          
      27    68    1.8560              2+                          
      28    69    1.8569              2+                          
      29    70    1.8712              1-                          
   Levels above 1.872 MeV were assumed to be overlapping.  Data of
   levels 6-8, 9-10 and 11-17 were lumped as is indicated in the  
   above table.  The direct inelastic scattering cross section was
   calculated also for the levels at 1.959, 2.372, 2.493, 3.112,  
   3.397, 3.6, 4.0, 4.5, 5.0, 5.5 and 6.0 MeV and added to mt=91. 
                                                                  
   Finally, the data for mt=51,52,53,54,55,56 and 91 were adjusted
   to reproduce the benchmark integral data/16/.                  
                                                                  
 mt=16, 17, 22, 28, 103, 104, 107                                 
        (n,2n), (n,3n), (n,na), (n,np), (n,p), (n,d), (n,a)       
   Theoretical calculation was made with sincros-ii.  The results 
   were normalized to                                             
        (n,2n)   2.161 b at 14.7 MeV measured by Qaim/17/,        
        (n,p)   0.0059 b at 14.7 MeV measured by Qaim/17/,        
   (n,d)+(n,np)  0.002 b at 14.7 MeV (systematics of Qaim/17/),   
        (n,a)    0.002 b at 14.7 MeV (systematics of Qaim/17/).   
                                                                  
 mt=102      Capture                                              
   Below 12 keV,  reproduced from the evaluated resolved resona-  
   nce parameters.                                                
   Above 12 keV, calculated with the casthy code/9/ and normalized
   to 72+-9 mb at 500 keV of voignier et al./18/.                 
   Above 3 MeV, a straight line in log-log scale was adopted      
   assuming 1.0 milli-barn at 14 MeV.                             
                                                                  
 mt=203   Total proton production                                 
   Sum of mt=28 and 103.                                          
                                                                  
 mt=204   Total deuteron production                               
   Equal to mt=104.                                               
                                                                  
 mt=207   Total alpha production                                  
   Sum of mt=22 and 107.                                          
                                                                  
mf=4  Angular distributions of secondary neutrons                 
 mt=2                                                             
   Calculated with the casthy code/9/.                            
 mt=51-58                                                         
   Calculated with the combined program of the casthy/9/ and      
   ecis/10/ codes.                                                
 mt=59-70                                                         
   Based on casthy2y calculation.                                 
                                                                  
mf=6  Energy-angle distributions of secondary particles           
 mt=16, 17, 22, 28, 91                                            
   Based on Kumabe's systematics/1,3/.                            
 mt=203,204,207                                                   
   Based on Kalbach's systematics/1,19/.                          
                                                                  
                                                                  
mf=12  Photon production multiplicities and transition probability
         arrays                                                   
 mt=22,51-70,102,103,107                                          
     Below 1.88238 MeV, given as multiplicities                   
     calculated with the egnash code/2/ and processed by the      
     gamfil2 code/20/.                                            
     mt=102 was calculated with the casthy code/10/.              
                                                                  
mf=13  Photon production cross sections                           
 mt=3                                                             
     Calculated with the egnash code/2/ and processed by the      
     gamfil2 code/20/.                                            
                                                                  
mf=14  Photon angular distributions                               
 mt=3,22,51-70,102,103,107                                        
     Assumed to be isotropic distributions                        
                                                                  
mf=15  Continuous photon energy spectra                           
 mt=3, 22, 102, 103, 107                                          
     Calculated with the egnash code/2/.                          
 mt=102                                                           
     Calculated with the casthy code/10/.                         
                                                                  
                                                                  
References                                                        
 1) Chiba, S. et al.: JAERI-M 92-027, p.35 (1992).                
 2) Yamamuro, N.: JAERI-M 90-006 (1990).                          
 3) Kumabe, I. et al.: Nucl. Sci. Eng., 104, 280 (1990).          
 4) ENSDF: Evaluated Nuclear Structure Data File, BNL/NNDC.       
 5) Camarda H.S. et al. : Phys. Rev. C8, 1813 (1973).             
 6) Ohkubo  M. : JAERI-M 5624 (1974).                             
 7) Macklin R.L. et al. : LA-9200-MS (1982).                      
 8) Mughabghab S.F. and Garber D.I. :"Neutron Cross Sections",    
    Vol.  2, Part B (1984).                                       
 9) Igarasi S. and Fukahori T.: JAREI 1321 (1991).                
10) Raynal J. : IAEA-SMR-9/8 p.281 (1972).                        
11) Delaroche J.F. et al. : 1979 Knoxville Conf. 336 (1979).      
12) Perey F.G.: Phys. Rev., 131, 745 (1963).                      
13) Aarthur, E.D. and Young, P.G.: LA-8626-MS (1980).             
14) Lohr J.M. and Haeberli W.: Nucl. Phys., A232, 381 (1974).     
15) Becchetti F.D. Jr. and Greenlees G.W.: "Polarization          
    Phenomena in Nucl. Reactions," Univ. Wisconsin Press, p.682   
    (1971).                                                       
16) Oyama, Y. et al.: JAERI-CONF 96-005, p70(1996).               
17) Qaim,S.M. and Graca, C.: Nucl. Phys., A242, 317 (1975).       
18) Voignier J. et al.: Nucl. Sci. Eng., 93, 43 (1986).           
19) Kalbach C. : Phys. Rev. C37, 2350(1988).                      
20) Hida K.: JAERI-M 86-150 (1986) (in Japanese).