26-Fe- 56

 26-Fe- 56 JNDC       EVAL-MAR87 S.IIJIMA,H.YAMAKOSHI             
                      DIST-MAY10                       20100316   
----JENDL-4.0         MATERIAL 2631                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
HISTORY                                                           
 87-03  Evaluation was performed for JENDL-3.                     
 87-05  Compiled by K.Shibata (jaeri).                            
 ******JENDL-3.2 *************************************************
 93-07  Modfifcation was made for (3,51-55),(3,59),(3,91).        
        Files 4 and 5 for mt=16,22,28,19 were obtained from the   
        file-6 of the JENDL Fusion File /1/.                      
        Data for (3,4) were reconstructed.                        
        (3,2) = total - nonelastic                                
 93-11  Data for (12,102) and (15,102) were reevaluated by        
        S. Igarasi (nedac).                                       
 94-03  As for (3,2) and (3,107), small cross-section values      
        were replaced with 0.0.                                   
        Data were compiled by K. Shibata (jaeri).                 
 *****************************************************************
                                                                  
 2000-04  Re-evaluated and compiled by K.Shibata (jaeri) for      
          JENDL-3.3.                                              
**************** modified parts for JENDL-3.3 ********************
 (1,451)     Modified.                                            
 (2,151)     Taken from Froehner's evaluation for JEF-2.          
 (3,1)       Re-evaluted.                                         
 (3,2)       Re-calculated.                                       
 (3,16)      Re-evaluated.                                        
 (3,102)     Pre-equilibrium capture was considered above 5 MeV.  
 (3,251)     Deleted.                                             
 (4,2)       Re-evaluated.  Transformation matrix deleted.        
 (4,16),(4,22),(4,28),(4,91)      Deleted.                        
 (5,16),(5,22),(5,28),(5,91)      Deleted.                        
 (6,16),(6,22),(6,28),(6,91)      Taken from JENDL/F-99 /1/.      
 (12,102),(15,102)                Between 27.5 and 570 keV,       
                                  based on experimental data.     
******************************************************************
 2002-01  Covariances were taken from JENDL-3.2 covariance file   
          except for MF/MT=3/1.                                   
                                                                  
 2008-10  Revised for JENDL-4 by K. Shibata (jaea)                
**************** modified parts for JENDL-4 **********************
 (1,451)    Comments modified                                     
 (3,1)      Re-calculated                                         
 (3,2)      Re-calculated                                         
 (3,4)      Re-calculated                                         
 (3,51)     Revised Hauser-Feshbach + coupled-channel calculations
            above 2.1 MeV                                         
 (3,52)     Revised Hauser-Feshbach + coupled-channel calculations
            in the whole energy range                             
 (3,53)     Revised Hauser-Feshbach + coupled-channel calculations
            in the whole energy range                             
 (4, 2)     Revised by taking account of experimental data and    
            model calculations                                    
******************************************************************
2010-03  Covariances were partly revised.                         
******************************************************************
 (33,1),(33,51),(33,53),(33,54),(33,55),(33,56),(33,58),(33,61),  
 (33,62),(33,63),(33,64),(33,65),(33,67),(33,73),(33,75),(33,77), 
 (33,91) revised                                                  
******************************************************************
                                                                  
 mf=1  General information                                        
   mt=451  Descriptive data and dictionary                        
                                                                  
 mf=2  Resonance parameters                                       
   mt=151 Resolved resonances                                     
       Resonance region = 1.0e-5 eV to 850.0 keV                  
       The Reich-Moore formula was used.  Paremeters were obtained
       from Froehner's evaluation for JEF-2 /2/.                  
                                                                  
       calculated 2200-m/s cross sections and res. integrals.     
                       2200-m/s     res. integ.                   
          elastic      12.08  b         -                         
          capture       2.590 b        1.348 b                    
          total        14.67  b         -                         
                                                                  
 mf=3  Neutron cross sections                                     
       Below 850 keV, background cross sections were given        
       for the elastic and capture cross sections.                
       Above 850 keV, cross sections were evaluated as follows.   
   mt=1    Total                                                  
       Between 850 keV and 7 MeV, fine structure measured by      
       Berthold et al./3/ was followd.  Above 7 MeV, the          
       cross sections were obtained from a least-squares fit to   
       the measurements /3,4,5/.                                  
       The contributions from Fe-54, 57, 58 were subtracted from  
       the measured cross sections of elemental iron.             
   mt=2    Elastic scattering                                     
       Given as total minus nonelastic cross sections.            
   mt=16,22,28  (n,2n),(n,n'a),(n,n'p)                            
       Calculated with gnash /6/.                                 
       For JENDL-3.3, the (n,2n) cross section was modified /7/   
       by considering the tng /8/ calculation.                    
   mt=4,51-77,91  Inelastic scattering                            
       The casthy and gnash calculations were adopted for         
       neutron energies below and above 7 MeV, respectively.      
       The direct-process component was considered for mt=        
       51,52,53,54,77 by the c.c. theory.                         
                                                                  
       Spherical optical model calculation was made by using      
       casthy code /9/.  parameters are as follows:               
            V  = 46.0-0.25*E              , r0=1.286, a0=0.620    
            Ws = 14.0-0.20*E              , rs=1.390, as=0.700    
            Vso= 6.0                      , rso=1.07, aso=0.620   
                  (energies in MeV, lengths in fm).               
                                                                  
       The level scheme is given as follows:                      
          no.     energy(MeV)  spin-parity                        
          g.s.      0.0          0 +                              
           1.       0.8468       2 +                              
           2.       2.0851       4 +                              
           3.       2.6576       2 +                              
           4.       2.9417       0 +                              
           5.       2.9600       2 +                              
           6.       3.1200       1 +                              
           7.       3.1229       4 +                              
           8.       3.3702       2 +                              
           9.       3.3884       6 +                              
          10.       3.4454       3 +                              
          11.       3.4493       1 +                              
          12.       3.6009       2 +                              
          13.       3.6019       2 +                              
          14.       3.6070       0 +                              
          15.       3.7480       2 +                              
          16.       3.7558       6 +                              
          17.       3.8320       2 +                              
          18.       3.8565       3 +                              
          19.       4.0940       3 +                              
          20.       4.1003       3 +                              
          21.       4.1200       4 +                              
          22.       4.2982       4 +                              
          23.       4.3020       0 +                              
          24.       4.3950       3 +                              
          25.       4.4010       2 +                              
          26.       4.4584       3 +                              
          27.       4.5100       3 -                              
       Continuum levels were assumed above 4.701 MeV.             
       ***** JENDL-3.2 *******************************************
       For mf/mt=3/51 between threshold and 2.1 MeV, evaluated    
       data were obtained from high resolution data of Voss et    
       al. /10/ by taking account of gamma-ray angular distri-    
       butions /11/.                                              
       The cross sections for mt=54,91 were replaced with those   
       contained in the JENDL Fusion File.                        
       As for mt=59, a point at 11.7 MeV was deleted.             
       Furthermore, the cross sections for mt=52-55 were modi-    
       fied around threshold by considering the measurements      
       /12,13/.                                                   
       ***********************************************************
       ***** JENDL-4 *********************************************
       Fort mt=51,52,53, Hauser-Feshbach + coupled-channel        
       calculations were performed with POD /20/ and OPTMAN /21/  
       codes by using the neutron potentials obtained by Kunieda  
       et al./22/                                                 
       As for mt=51, experimentally determined resonance cross    
       sections were kept from the threhold to 2.1 MeV.           
       ***********************************************************
                                                                  
   mt=102  Capture                                                
       Below 850 keV, background is given.  Above 850 keV,        
       For JENDL-3.3, the pre-equilibrium capture process was     
       taken into account /7/.                                    
   mt=103  (n,p)                                                  
       Below 7 MeV, based on the data of Smith and Meadows/14/.   
       7 - 13 MeV, taken from JENDL-2.                            
       13 - 16 MeV, based on the data of Ikeda et al./15/         
       16 - 20 MeV, taken from JENDL-2.                           
   mt=107  (n,alpha)                                              
       Based on experimental data.                                
   mt=203  Proton production                                      
       Sum of mt=28 and 103.                                      
   mt=207  Alpha production                                       
       Sum of mt=22 and 107.                                      
                                                                  
 mf=4  Angular distributions of secondary neutrons                
   mt=2,51-77                                                     
       Optical and statistical-model calculations were adopted.   
       the c.c. calculations were added to the levels of mt=51,52,
       53,54,77.                                                  
       For JENDL-3.3, above 10 MeV, mt=2 data were replaced with  
       the optical model calculations using the neutron potentials
       determined by Arthur and Young. /16/                       
       ***** JENDL-4 *********************************************
       For mt=2, the Legendre coefficients were revised by        
       taking account of fine-resolution experimental data /23,24/
       and Hauser-Feshbach + coupled-channel optical model        
       calculations.  The experimental data were averaged in the  
       energy interval of 5 or 10 keV between 40 keV and 2.5 MeV. 
       Above 2.5, new model calculations were adopted.            
       ***********************************************************
 mf=6  Energy-angle distributions of secondary particles          
   mt=16,22,28,91                                                 
       Obtained from JENDL Fusion File (sincros-II/17/ cal-       
       culations).                                                
                                                                  
 mf=12 Photon multiplicities and transition probability arrays    
   mt=16,22,28,91,103,107                                         
       Multiplicities were calculated with gnash.                 
   mt=102                                                         
       Calculated with casthy.                                    
       For 27.5 keV and 570 keV, based on experimental data       
       measured by Igashira et al./18/                            
                                                                  
 mf=14 Photon angular distributions                               
   mt=16,22,28,51-77,91,102,103,107                               
       Assumed to be isotropic.                                   
                                                                  
 mf=15 Photon energy distributions                                
   mt=16,22,28,91,103,107                                         
       Calculated with gnash.                                     
   mt=102                                                         
       Calculated with casthy.                                    
       For 27.5 keV and 570 keV, based on experimental data       
       measured by Igashira et al./18/                            
                                                                  
mf=33 Covariances of cross sections (ref.19)                      
  mt=1                                                            
      Based on experimental data/3,4,5/.  A chi-value was 1.96.   
      ***** JENDL-4 **********************************************
      Below 850 keV, the covariances were firstly estimated from  
      the experimental data /24-28/.  Then, the estimated         
      variances were modified by considering the difference       
      between the average of the experimental data and that of the
      total cross section in JENDL-4.  Above 850, the covariances 
      in JENDL-3.3 were used, although the variances were         
      increased by comparing with the experimental data/3,4.5/.   
      No correlation was assumed between the region below 850 keV 
      and that above 850 keV.                                     
      ************************************************************
  mt=2                                                            
      Constructed from mt=1, 16, 22, 28, 51-91, 102, 103, and 107.
  mt=4                                                            
      Constructed from mt=51-77,91.                               
  mt=16                                                           
      the covariances were obtained by using kalman.  A chi-value 
      was 0.7.                                                    
  mt=22                                                           
      The covariances were obtained by using kalman.  A chi-value 
      was 0.7.                                                    
  mt=28                                                           
      The covariances were obtained by using kalman.  A chi-value 
      was 0.7.                                                    
  mt=51-77,91                                                     
      The covariances were obtained by using kalman.  A chi-value 
      was 1.9.                                                    
      ************************************************************
      In JENDL-4, variances for MT=51,53,54,55,56,58,61,62,63,64, 
      65,67,73,75,77,91 were revised by considering the spread of 
      experimental data.                                          
      ************************************************************
  mt=102                                                          
      The covariances were obtained by using kalman.  A chi-value 
      was 2.45.                                                   
  mt=103                                                          
      Based on experimental data.  A chi-value was 4.99.          
  mt=107                                                          
      The covariances were obtained by using kalman.  A chi-value 
      was 0.7.                                                    
                                                                  
mf=34 Covariances of angular distributions (ref.19)               
  mt=2                                                            
      The covariances of p1 coefficients were obtained by using   
      kalman.  A chi-value was 1.95.                              
                                                                  
                                                                  
References                                                        
 1) Chiba S. et al.: JAERI-M 92-027, p.35 (1992).                 
 2) Nordborg C. and Salvatores M.: Proc. Int. Conf. Nuclear Data  
     for Science and Technology, Gatlinburg 1994, Vol.2, p.680    
     (1994).                                                      
 3) Berthold K. et al.: Taken from EXFOR (1995).                  
 4) Carlson A.D. and Cerbone R.J.: Nucl. Sci. Eng., 42, 28        
     (1970).                                                      
 5) Perey F.G. et al.: ORNL-4823 (1972).                          
 6) Young P.G. and Arthur E.D.: LA-6974 (1977).                   
 7) Shibata K.: Private communication (2000).                     
 8) Shibata K. and Fu. C.Y.: ORNL/TM-10093 (1986).                
 9) Igarasi S. : J. Nucl. Sci. Technol., 12, 67 (1975).           
10) Voss F. et al.: Proc. Third Conf. on Neutron Cross Sections   
    and Technology, 1971, Knoxville, p.218 (1971).                
11) Smith D.L.: ANL/NDM-20 (1976).                                
12) Hopkins J.C. and Silbert M.G.: Nucl. Sci. Eng.19,431(1964).   
13) Gilboy W.B. and Towle J.H.: Nucl. Phys., 64, 130 (1965).      
14) Smith D.L. and Meadows J.W.: Nucl. Sci. Eng., 58, 314 (1975). 
15) Ikeda Y. et al.: JAERI 1312 (1988).                           
16) Arthur E.D. and Young P.G.: LA-8626-MS (1980).                
17) Yamamuro N.: JAERI-M 90-006 (1990).                           
18) Igashira M. et al.: Proc. Int. Conf. Nuclear Data for         
     Science and Technology, Mito 1988, p.67 (1988).              
19) Shibata K. et al.: JAERI-Research 97-074 (1997).              
20) Ichihara A. et al.: JAEA-Data/Code 2007-012 (2007).           
21) Soukhovitski E.Sh. et al.: JAERI-Data/Code 2005-002 (2005).   
22) Kunieda S. et al.: J. Nucl. Sci. Technol., 44, 838 (2007).    
23) Kinney W.E. and McConnell J.W.: Proc. Int. Conf. Interactions 
    of Neutrons with Nuclei, Lowell 1976, p.1319 (1976).          
24) Perey C.M. et al.: Proc. Int. Conf. Nuclear Data for Science  
    and Technology, Juelich 1991, p.41 (1992).                    
25) Harvey J.A. et al.: DOE-NDC-33, 142 (1984).                   
26) Shcherbakov O.A. et al.: Yadernye Konstanty, 25, 51 (1977).   
27) Vinogradov V.N. et al.: Yadernye Fizika, 26, 936 (1977).      
28) Havens,Jr. W.W and Rainwater L.J.: Phys. Rev., 83,1123 (1951).