68-Er-166

 68-ER-166 TIT        EVAL-SEP00 A.K.M.HARUN-AR-RASHID+           
                      DIST-MAR02                       20020205   
----JENDL-3.3         MATERIAL 6837                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
HISTORY                                                           
2000-09 Evaluation was performed by A.K.M.Harun-ar-Rashid (tit),  
        M.Igashira (tit), T.Ohsaki (tit), and K.Shibata (jaeri).  
2001-01 Compiled by K.Shibata (jaeri).                            
                                                                  
 mf=1  General information                                        
   mt=451  Descriptive data and dictionary                        
                                                                  
 mf=2  Resonance parameters                                       
   mt=151 Resolved resonances                                     
     Resonance range (1.0e-05 to 3000.0 eV).                      
     Resolved resonance parameters from Ref.1 or 2 (Ehi=3000.0 eV)
     The bound level at -40.4 eV has Gamma-n = 0.3953 eV and      
     Gamma-gamma = 0.092 eV.  This choice gives the desired       
     value for the thermal capture cross section, 16.2 b.         
     Values of Gamma-gamma not given in Ref.1 or 2 are set to     
     0.092 eV.                                                    
     The value for the scattering radius is 0.8295, taken from    
     Ref.3 with small change within the given error, so as to     
     reproduce the close value of the thermal neutron scattering  
     cross section recommended by mughabghab [3].                 
     The highest energy resonance included is 2931.8 eV           
     No background cross section is given.                        
                                                                  
     Calculated 2200-m/s cross sections and res. integrals        
                  2200-m/s         res. integ.                    
      elastic    12.448 b             -                           
      capture    16.765 b           112.16 b                      
      total      29.213 b             -                           
                                                                  
 mf=3  Neutron cross sections                                     
   mt=  1  Total cross section                                    
     Spherical optical model calculation was made by using        
     casthy code [ref.4].  Parameters are as follows,             
            V  = 48.2-0.25*E-16.0*(N-Z)/A , r0=1.18,   a0=0.63    
            Ws = 7.84+0.51*E              , rs=1.29,   as=0.63    
            Vso= 6.0                      , rso=1.26,  aso=0.63   
                  (energies in MeV, lengths in fm).               
                                                                  
   mt=  2  Elastic scattering cross section                       
      The cross sections were obtained by subtracting a sum of    
      reaction cross sections from the total cross sections.      
                                                                  
   mt=  4,51,52,.,.,74,91  Inelastic scattering cross sections    
      Calculated by using egnash code [5,6].                      
      The direct-process component was considered for mt=51       
      from dwba calculation by dwucky code. [5,7]                 
      The level scheme is given as follows:                       
                                                                  
      no    energy  spin  parity                                  
      g.s  0.00000   0.0     +                                    
       1   0.08060   2.0     +                                    
       2   0.26500   4.0     +                                    
       3   0.54550   6.0     +                                    
       4   0.78590   2.0     +                                    
       5   0.85940   3.0     +                                    
       6   0.91120   8.0     +                                    
       7   0.95620   4.0     +                                    
       8   1.07530   5.0     +                                    
       9   1.21600   6.0     +                                    
      10   1.34960  10.0     +                                    
      11   1.37600   7.0     +                                    
      12   1.45820   2.0     -                                    
      13   1.45990   0.0     +                                    
      14   1.51340   3.0     -                                    
      15   1.52840   2.0     +                                    
      16   1.55570   8.0     +                                    
      17   1.57220   4.0     -                                    
      18   1.59620   4.0     -                                    
      19   1.66240   1.0     -                                    
      20   1.66580   5.0     -                                    
      21   1.67880   4.0     +                                    
      22   1.69230   5.0     -                                    
      23   1.70310   2.0     +                                    
      24   1.78700   6.0     -                                    
    Levels above 1.8 MeV are assumed to be overlapping            
                                                                  
   mt=  16,17,22,28,32,103,104,105,107                            
           (n,2n), (n,3n), (n,n'a), (n,n'p), (n,n'd)              
           (n,p), (n,d), (n,t), (n,a)                             
      Calculated  using egnash [5,6].                             
                                                                  
   mt=102  Capture cross secton                                   
      The capture cross section is based on the statistical model 
      calculations.  The measured data of Ref.8 were taken into   
      account. The direct and semidirect capture cross sections   
      were added above 2 MeV by using the quick gnash code [6,9]. 
                                                                  
 mf=4  Angular distributions of secondary neutrons                
   mt=2                                                           
      Calculated with the casthy code.                            
   mt=16,17,22,28,32,                                             
      Assumed to be isotropic in the laboratory system.           
   mt=51,---,74,91                                                
      Calculated with the casthy code.                            
      For mt=51, the dwba component was taken into account.       
                                                                  
 mf=5  Energy distributions of secondary neutrons                 
   mt=16,17,22,28,32,91                                           
      Calculated with the egnash code.                            
                                                                  
 mf=12  Photon production multiplicities                          
   mt=16,17,22,28,51-74,91,102,103,104,107                        
      Calculated with the egnash code.                            
                                                                  
 mf=14  Photon angular distributions                              
   mt=16,17,22,28,51-74,91,102,103,104,107                        
      Assumed to be isotropic.                                    
                                                                  
 mf=15  Photon energy distributions                               
   mt=16,17,22,28,91,102,103,104,107                              
      Calculated with the egnash code.                            
      For mt=102, the measured data [10] were included at 45 and  
      550 keV.                                                    
                                                                  
References                                                        
  1. Landolt-Boernstein New Series I/16B (Aug 1998).              
  2. Y. Danon et al.: Nucl. Sci. Eng., 28, 61 (1998).             
  3. S. F. Mughabghab: "Neutron Cross Sections: Vol. 1,           
     Neutron Resonance Parameters and Thermal Cross Sections,     
     Part B: z=61-100," Academic Press (1984).                    
  4. S. Igarasi, T. Fukahori: JAERI-1321 (1991).                  
  5. N. Yamamuro: JAERI-M 90-006 (1990).                          
  6. P.G. Young et al.: LA-12343-MS, UC-413 ( 1992).              
  7. P.D. Kunz: Program Dwuck4, Computational Nuclear             
     Physics 2: Nuclear Reaction; edited by K. Langanke et al.,   
     published by Springer-Verlag (1992).                         
  8. A.K.M. Harun-Ar-Rashid et al.: JAERI-CONF 2000-005, pp.131   
     (2000),                                                      
  9. N. Yamano: Private communication.                            
 10. M. Igashira: Private communication (2001).