51-Sb-121

 51-SB-121 JNDC       EVAL-AUG89 JNDC FP NUCLEAR DATA W.G.        
                      DIST-MAR02 REV3-JUL01            20010726   
----JENDL-3.3         MATERIAL 5125                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
HISTORY                                                           
84-10 Evaluation for JENDL-2 was made by JNDC FPND W.G./1/        
89-08 Modification for JENDL-3 was made/2/.                       
94-02 JENDL-3.2                                                   
      Capture cross section modified by JNDC FPND WG.             
      Other data were adopted from JENDL fusion file.             
      Compiled by T.Nakagawa                                      
                                                                  
     *****   modified parts for JENDL-3.2   ********************  
      All cross sections except (3,105).                          
          (3,32) and (3,33) were deleted.                         
      All angular distributions except for (4,2).                 
      All energy distributions.                                   
     ***********************************************************  
     -------------------------------------------------------------
      JENDL fusion file /3/  (as of Feb. 1994)                    
            Evaluated by K.Kosako (nedac) and S. Chiba (ndc/jaeri)
            Compiled  by K.Kosako.                                
                                                                  
      -  The inelastic scattering cross sections and angular      
         distributions of inelastically scattered neutrons (except
         continuum inelastic) were calculated with casthy2y and   
         dwucky in sincros-ii system/4/ 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.  
      -  The (n,t) reaction cross section, resonance parameters   
         and ang. distributions of elastically scattered neutrons 
         were taken from JENDL-3.1.                               
      -  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 /5/ using f15tob /3/.  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./4/.     
         Level schemes were determined on the basis of ENSDF/6/.  
     -------------------------------------------------------------
01-07 JENDL-3.3                                                   
      Compiled by K.Shibata                                       
                                                                  
      *****   modified parts for JENDL-3.3   *********************
      (1,451)      Updated.                                       
      (3,251)      Deleted.                                       
      (4,2)        Transformation matrix deleted.                 
      (4,16-28)    Deleted.                                       
      (4,91)       Deleted.                                       
      (5,16-91)    Deleted.                                       
      (6,16-207)    Taken from JENDL fusion file                  
      ************************************************************
                                                                  
mf = 1  General information                                       
  mt=451 Comments and dictionary                                  
                                                                  
mf = 2  Resonance parameters                                      
  mt=151 Resolved and unresolved resonance parameters             
  Resolved resonance region (MLBW formula) : below 2 keV          
    Resonance parameters of JENDL-2/1/ were revised except for    
    radiation widths.                                             
       Evaluation of JENDL-2 was made on the basis of the data    
    measured by Bolotin and Chrien/7/, Wynchank et al./8/,        
    Muradjan et al./9/, Adamchuk et al./10/ and Ohkubo et al.     
    /11/  Neutron orbital angular momentum L and total spin J     
    were based on the data by Bhat et al./12/ and Cauvin et al.   
    /13/ The average radiation width of 0.089 eV was deduced and  
    applied to the levels whose radiation width was unknown.      
    After that, new experimental data for neutron widths and      
    total spin J were published by Ohkubo et al./14/ and Beliaev  
    et al./15/, respectively.                                     
       Evaluation of JENDL-3 was performed on the basis of the    
    new data for the neutron widths and spin J and JENDL-2 for    
    the radiation widths.  Total spin J of some resonances was    
    tentatively estimated with a random number method.  Neutron   
    orbital angular momentum L was estimated with a method of     
    Bollinger and Thomas/16/.  Scattering radius of 6.0 fm was    
    assumed from the systematics of measured values for           
    neighboring nuclides.                                         
                                                                  
  Unresolved resonance region : 2 keV - 100 keV                   
    The neutron strength function S0 was based on the compilation 
    of Mughabghab et al./17/, and S1 and S2 were calculated with  
    optical model code casthy/18/.  The observed level spacing was
    determined to reproduce the capture cross section calculated  
    with casthy.  The effective scattering radius was obtained    
    from fitting to the calculated total cross section at 100 keV.
    The radiation width was based on the compilation of Mughabghab
    et al.                                                        
                                                                  
  Typical values of the parameters at 70 keV:                     
    S0 = 0.300e-4, S1 = 2.700e-4, S2 = 0.760e-4, Sg = 59.8e-4,    
    Gg = 0.100 ev, R  = 5.838 fm.                                 
                                                                  
  calculated 2200-m/s cross sections and res. integrals (barns)   
                     2200 m/s               res. integ.           
      total           9.582                    -                  
      elastic         3.590                    -                  
      capture         5.991                   214                 
                                                                  
mf = 3  Neutron cross sections                                    
  Below 100 keV, resonance parameters were given.                 
                                                                  
  For JENDL-3.1, above 100 keV, the spherical optical and         
  statistical model calculation was performed with casthy, by     
  taking account of competing reactions, of which cross sections  
  were calculated with pegasus/19/ standing on a preequilibrium   
  and multi-step evaporation model.  The omp's for neutron given  
  in table 1 were determined so as to reproduce a systematic trend
  of the total cross section by changing rso of Iijima-Kawai      
  potential/20/. The omp's for charged particles are as follows:  
     proton   = Perey/21/                                         
     alpha    = Huizenga and igo/22/                              
     deuteron = Lohr and Haeberli/23/                             
     helium-3 and triton = Becchetti and Greenlees/24/            
  Parameters for the composite level density formula of Gilbert   
  and Cameron/25/ were evaluated by Iijima et al./26/  More       
  extensive determination and modification were made in the       
  present work.  Table 2 shows the level density parameters used  
  in the present calculation.  Energy dependence of spin cut-off  
  parameter in the energy range below E-joint is due to Gruppelaar
  /27/.                                                           
                                                                  
  For JENDL-3.2, all cross section data except for the elastic    
  scattering, capture and (n,t) were adopted from JENDL fusion    
  file.  The calculation was made with sincros-ii system/4/ by    
  adopting Walter-Guss omp modified by Yamamuro/4/ for neutron,   
  Perey omp /28/ for Proton, Lemos omp modified by Arthur and     
  Young/29/ for alpha, Lohr-Haeberli omp/30/ for deuteron,        
  Becchettii-Greenlees omp/24/ for triton and he-3, and standard  
  level density parameters of sincros-ii system.                  
                                                                  
  mt = 1  Total                                                   
    Spherical optical model calculation with the modified Walter- 
    Guss omp/4/ was adopted.                                      
                                                                  
  mt = 2  Elastic scattering                                      
    Calculated as (total - sum of partial cross sections).        
                                                                  
  mt = 4, 51 - 91  Inelastic scattering                           
    The cross sections were taken from JENDL fusion file.  The    
    level scheme was based on ref./6/  Contributions of the       
    direct process were calculated for the levels marked with '*'.
                                                                  
           no.      energy(MeV)    spin-parity (direct process)   
           gr.       0.0            5/2 +                         
            1        0.0371         7/2 +          *              
            2        0.5076         3/2 +          *              
            3        0.5731         1/2 +          *              
            4        0.9470         9/2 +          *              
            5        1.0240         7/2 +          *              
            6        1.0354         9/2 +                         
            7        1.1393        11/2 +                         
            8        1.1447         7/2 +          *              
            9        1.3862         9/2 +                         
           10        1.4075         5/2 +                         
           11        1.4105         7/2 +                         
           12        1.4272         9/2 +          *              
           13        1.4480         1/2 -                         
         Levels above 1.449 MeV were assumed to be overlapping.   
                                                                  
  mt = 102  Capture                                               
    Spherical optical and statistical model calculation with      
    casthy was adopted.  Direct and semi-direct capture cross     
    sections were estimated according to the procedure of Benzi   
    and Reffo/31/ and normalized to 1 milli-barn at 14 MeV.       
                                                                  
    The gamma-ray strength function (54.5e-4) was adjusted to     
    reproduce the capture cross section of 110 milli-barns at 1   
    MeV which was an average value of experimental data of        
    Trofimov/32/ and our previous evaluation normalized to 150 mb 
    at 500 keV/33/.                                               
                                                                  
  mt = 16  (n,2n) cross section                                   
  mt = 17  (n,3n) cross section                                   
  mt = 22  (n,n'a) cross section                                  
  mt = 28  (n,n'p) cross section                                  
  mt =103  (n,p) cross section                                    
  mt =104  (n,d) cross section                                    
  mt =107  (n,alpha) cross section                                
   Adopted from JENDL fusion file.  Theoretical calculation was   
   made with sincros-ii.  The results were normalized to          
                                                                  
  (n,d)+(n,np) 0.00415 b at 14.5 MeV (systematics of Forrest/34/),
        (n,a)   0.0036 b at 14.9 MeV (systematics of Konno+/35/). 
                                                                  
   and the (n,2n) cross section was adjusted to the energy        
   distributions of emitted neutrons (a factor of 1.27 was        
   applied).                                                      
                                                                  
  mt =105  (n,t) cross section                                    
    This reaction cross section was calculated with the           
    preequilibrium and multi-step evaporation model code pegasus. 
                                                                  
    The kalbach's constant k (= 145.3) was estimated by the       
    formula derived from Kikuchi-Kawai's formalism/36/ and level  
    density parameters.                                           
                                                                  
  mt=203   Total proton production                                
    Sum of mt=28 and 103.                                         
                                                                  
  mt=204   Total deuteron production                              
    Equal to mt=104.                                              
                                                                  
  mt=205   Total triton production                                
    Equal to mt=105.                                              
                                                                  
  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/20/.                           
 mt=51-63                                                         
   Taken from JENDL fusion file.                                  
                                                                  
mf = 6  Energy-angle distributions of secondary particles         
 mt=16, 17, 22, 28, 91, 203, 204, 205, 207                        
   Taken from JENDL fusion file.                                  
                                                                  
                                                                  
<< The parameters used in the casthy and pegasus calculations. >> 
                                                                  
Table 1  Neutron optical potential parameters                     
                                                                  
                depth (MeV)       radius(fm)    diffuseness(fm)   
         ----------------------   ------------  ---------------   
        V  = 47.64-0.473E         r0 = 6.256    a0 = 0.62         
        Ws = 9.744                rs = 6.469    as = 0.35         
        Vso= 7.0                  rso= 6.241    aso= 0.62         
  The form of surface absorption part is der. Woods-Saxon type.   
                                                                  
Table 2  Level density parameters                                 
                                                                  
 nuclide  syst a(1/MeV)  t(MeV)    c(1/MeV)  Ex(MeV)   pairing    
 ---------------------------------------------------------------  
 49-In-117     1.678e+01 6.010e-01 2.387e+00 5.208e+00 1.150e+00  
 49-In-118  *  1.804e+01 6.064e-01 3.111e+01 4.636e+00 0.0        
 49-In-119     1.940e+01 5.340e-01 2.195e+00 4.999e+00 1.240e+00  
 49-In-120  *  1.757e+01 6.016e-01 2.330e+01 4.366e+00 0.0        
                                                                  
 50-Sn-118     1.633e+01 6.140e-01 3.341e-01 6.448e+00 2.340e+00  
 50-Sn-119     1.635e+01 5.990e-01 1.772e+00 5.050e+00 1.190e+00  
 50-Sn-120     1.595e+01 6.540e-01 4.691e-01 7.083e+00 2.430e+00  
 50-Sn-121     1.630e+01 6.100e-01 2.010e+00 5.217e+00 1.190e+00  
                                                                  
 51-Sb-119  *  1.858e+01 6.040e-01 5.801e+00 5.944e+00 1.150e+00  
 51-Sb-120  *  1.834e+01 6.016e-01 3.366e+01 4.659e+00 0.0        
 51-Sb-121     1.730e+01 5.740e-01 1.715e+00 5.022e+00 1.240e+00  
 51-Sb-122     1.772e+01 5.500e-01 1.346e+01 3.517e+00 0.0        
 ---------------------------------------------------------------  
  syst:  * = ldp's were determined from systematics.              
                                                                  
 Spin cutoff parameters were calculated as 0.146*sqrt(a)*a**(2/3).
 In the casthy calculation, spin cutoff factors at 0 MeV were     
 assumed to be 9.25 for Sb-121 and 5.0 for Sb-122.                
                                                                  
References                                                        
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    and Applied Science, Santa Fe., Vol. 2, p.1627 (1985).        
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    (1983).                                                       
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    (1971).                                                       
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    (1965).                                                       
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27) Gruppelaar, H.: ECN-13 (1977).                                
28) Perey, F.G.: Phys. Rev., 131, 745 (1963).                     
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30) Lohr, J.M. and Haeberli W.: Nucl. Phys., A232, 381 (1974).    
31) Benzi, V. and Reffo, G.: CCDN-NW/10 (1969).                   
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    1987, Vol. 3, p.331 (1987).                                   
33) Tolstikov, V.A., et al.: Atomnaya Energiya, 24, 576 (1968).   
34) Forrest, R.A.: AERE-R 12419 (1986).                           
35) Konno, C. et al.: JAERI 1329 (1993).                          
36) Kikuchi, K. and Kawai, M.: "Nuclear Matter and Nuclear        
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