31-Ga- 71

 31-GA- 71 KHI        EVAL-MAR94 T.WATANABE                       
                      DIST-MAR02 REV2-FEB02            20020208   
----JENDL-3.3         MATERIAL 3131                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
HISTORY                                                           
94-3  Newly evaluated.                                            
00-10 JENDL-3.3                                                   
      Compiled by K.Shibata (jaeri)                               
***** Modified parts for JENDL-3.3 ****************************** 
(1,451)             Updated.                                      
(3,251)             Deleted.                                      
(4,2)               Transformation matrix deleted.                
(5,16-91)           Modified.                                     
***************************************************************** 
                                                                  
mf=1  General information                                         
  mt=451 Comments and dictionary                                  
                                                                  
mf=2  Resonance parameters                                        
  mt=151 Resolved resonance parameters                            
  Resolved resonance parameters for MLBW formula (below 5.6keV)   
  Negative energy level parameters were adjusted to reproduce     
  Koesters 2200m/s data/1/.                                       
  Resonance parameterd were evaluatred mainly based on Ohkubo's   
  data/2/ and Mughabghabs compilation/3/.                         
                                                                  
  calculated 2200-m/s cross sections and res. integrals (barns)   
                     2200 m/s               res. integ.           
      total           8.945                    -                  
      elastic         5.236                    -                  
      capture         3.709                   32.19               
                                                                  
mf=3  Neutron cross sections                                      
  Below 5.6 keV, resonance parameters were given.                 
  Above 5.6 keV, the total, elastic and inelastic scattering, and 
  capture cross sections were calculated with the optical and     
  statistical model code casthy/4/.                               
  Optical model parameters used in casthy calcualtion were as     
  follows.                                                        
                                                                  
                depth (MeV)       radius(fm)    diffuseness(fm)   
         ----------------------   ------------  ---------------   
     V  = 49.42-0.5867E         , r0 =  5.3541     , a0 =  0.415  
     Ws = 5.381+0.4117E         , rs =  5.4162     , as =  0.456  
     Vso= 8.552                 , rso=  6.5549     , aso=  0.648  
                                                                  
  The level scheme was adopted from ENSDF file/5/.                
           no.      energy(MeV)    spin-parity  beta2/beta3       
           gr.       0.0            3/2 -                         
            1        0.3900         1/2 -       0.2               
            2        0.4872         5/2 -       0.2               
            3        0.5116         3/2 -       0.2               
            4        0.7140        11/2 -                         
            5        0.9103         3/2 -       0.2               
            6        0.9648         5/2 -       0.15              
            7        1.1074         7/2 -       0.15              
            8        1.1093         1/2 -       0.15              
            9        1.3952         7/2 -       0.15              
           10        1.4759         5/2 -       0.1               
           11        1.4937         9/2 +       0.1               
           12        1.4986         5/2 -                         
           13        1.6316         3/2 -                         
           14        1.7022         1/2 +                         
           15        1.7198         5/2 -                         
           16        1.7524         3/2 -                         
           17        1.9040         5/2 -                         
           18        1.9410         3/2 +                         
           19        1.9950         5/2 -                         
           20        2.0640         1/2 -                         
           21        2.1324         5/2 -                         
           22        2.1913         5/2 -                         
           23        2.2060         5/2 -                         
           24        2.2472         7/2 +                         
           25        2.2944         1/2 -                         
           26        2.3273         1/2 -                         
      Levels above 2.33 MeV were assumed to be overlapping.       
                                                                  
  Parameters for the composite level density formula of Gilbert-  
  Cameron were evaluated.                                         
  Spin cut-off parameter C1 was taken as 0.146.                   
                                                                  
                                   Ga- 71      Ga- 72             
                                 --------    --------             
          a (1/MeV)                13.000      12.900             
          spin cut-off param.       9.026       9.075             
          pairing energy (MeV)      1.430       0.0               
          normalization factor    1747.70     1758.60             
          E-joint (MeV)             6.326       4.961             
                                                                  
  The capture cross section was normalized to 12 mb at 1MeV to    
  reproduce the experimental capture cross section/6/.            
  Above 1 MeV, direct/semidirect capture cross section normalized 
  to 0.74mb were added to casthy's results/7/.                    
                                                                  
  mt=16,17,22,28,32,103,104,105,106,107                           
     (n,2n),(n,3n),(n,na),(n,np),(n,nd),(n,nt),(n,p),(n,d),       
     (n,t),(n,he-3),(n,a)                                         
  were evaluated with modified egnash-2/8/ using f2=0.6 and       
  following optical potential                                     
     neutron   :same as used in casthy                            
     proton    :Perey's omp/9/                                    
     deutron   :Lohr-Haeberli's omp/10/                           
     triton    :Becchetti-Greenlees omp/11/                       
     he-3      :Becchetti-Greenlees omp/11/                       
     alpha     :Lemos omp/12/                                     
  and normalized to following data.                               
     (n,2n)    950.0    mb      Csikai's data/13/                 
     (n,na)      2.4    mb      Qaims data/14/                    
     (n,np)      1.95   mb      systematics/15/                   
     (n,p)      20.5    mb      Qaims data/16/                    
     (n,d)       3.63   mb      systematics                       
     (n,t)       0.33   mb      systematics                       
     (n,a)       3.5    mb      measured data/17,18/              
                                                                  
mf=4  mt=2,16,17,22,28,32,51-76,91                                
  (n,2n),(n,na),(n,np),(n,nd) and elastic and inelastic scattering
  angular distributions of secondary neutrons                     
  Angular distributions were calculated with casthy for ela-      
  stically and inelastically scattered neutrons.                  
  Direct inelastic scattering contributions were evaluated with   
  dwucky/19/ and added to casthy's results.                       
  Deformation parameters used in the dwucky calculation was       
  evaluated from compilation/20,21/ and ENSDF half life data.     
  As for (n,2n),(n,3n),(n,na),(n,np) and (n,nd),isotropic         
  distributions were assumed.                                     
                                                                  
mf=5  Energy distributions of secondary neutrons                  
  mt=16,17,22,28,32,91                                            
  For (n,2n),(n,3n),(n,na),(n,np),(n,nd) and continum inelastic   
  scattering, secondary neutron energy distributions were         
  calculated with egnash-2.                                       
  ****************************************************************
  For JENDL-3.3, distributions at threshold were modified.        
  ****************************************************************
                                                                  
References                                                        
 1)L.Koester et. al.       Z.Phys. A318,347(1984)                 
 2)M.Ohkubo et. al.        JAERI-M 90-213(1990)                   
 3)S.F.Mughabghab et. al., Neutron Cross Section Vol.1 Part A     
                           Academic Press(1981)                   
 4)S.Igarasi,T.Fukahori    JAERI-1321    (1991)                   
 5)Evaluated Nuclear Structural Data File                         
 6)G.G.Zaikin et al.       UFZ 16,1205(1971)                      
 7)T.Nakagawa              CAPDIR manual                          
 8)N.Yamamuro              JAERI-M 90-006(1991)                   
 9)F.G.Perey               Phys. Rev. 131, 745(1963)              
10)J.M.Lohr,W.Haeberli     Nucl. Phys. A232, 381(1974)            
11)F.D.Becchetti  and      Polarization Phenomena in Nuclear      
     G.W.Greenless         Reaction   682(1971) Univ. Wisconsin   
12)O.F.Lemos               Orsay Rep.Ser.A No.136(1972)           
13)J.Csikai et al.         AHP 23,87(1967)                        
14)S.M.Qaim et al.         EUR-5182e,939'1974)                    
15)R.A.Forrest             AERE-R 12419(1986)                     
16)S.M.Qaim et al          Nucl. Phys. A283,269(1977)             
17)K.Kawade et.al.         JAERI-M 90-171(1990)                   
18)S.M.Qaim                14 MeV Activation Cross Sections       
                           Handbook of Spectroscopy,Vol.3 p.141   
                           CRC Press BOCA Raton Florida,1981      
19)N.Yamamuro              JAERI-M 88-140(1988)                   
20)S.Raman et.al.          AND 42,1(1989                          
21)R.H.Spear               AND 42,55(1989)