37-Rb- 87

 37-Rb- 87 JAEA       EVAL-AUG09 K.Shibata, A.Ichihara, S.Kunieda 
                      DIST-MAY10                       20091118   
----JENDL-4.0         MATERIAL 3731                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
History                                                           
09-08 Evaluated by K. Shibata, A. Ichihara and S. Kunieda.        
09-10 Compiled by K. Shibata.                                     
                                                                  
MF= 1 General information                                         
  MT=451 Descriptive data and directory                           
                                                                  
MF= 2  Resonance parameters                                       
  MT=151 Resolved and unresolved resonance parameters             
    Resolved resonance region (MLBW formula) : below 12.46 keV    
      Resonance parameters of JENDL-2 were modified as follows :  
      Evaluation of JENDL-2 was performed on the basis of the data
      measured by Ohkubo et al./1/  Among 30 levels measured in   
      the energy region up to 49 keV, 28 levels were assumed to be
      s-wave, and remaining 2 levels at 267.1 and 376.9 eV to be  
      p-wave.  Neutron widths were determined from the 2g*(neutron
      width) measured by Ohkubo et al.  However, the value of     
      total spin J for each resonance level was unknown except    
      only 6 levels assigned by Ohkubo et al.  The target spin of 
      1.5 was adopted for these unknown levels instead of J.      
      Radiation width was obtained to be 166+-8 meV for only one  
      resonance level at 376.9 eV from the measurement by Ohkubo  
      et al. Average radiation width was also estimated to be     
      166+-30 meV by Ohkubo et al., and was adopted for the other 
      levels.                                                     
                                                                  
      For JENDL-3, the total spin J of 24 resonance levels was    
      tentatively estimated with a random number method.  Neutron 
      widths of these levels were modified on the basis of the    
      estimated J-values.  Radiation width of the 2nd level at    
      376.9 eV and average radiation width were also modified to  
      115.33 and 115.0 meV, respectively, so as to reproduce the  
      thermal capture cross section of 120+-30 mb given           
      by Mughabghab et al./2/  Scattering radius was taken from   
      the graph (Fig. 1, part A) given by Mughabghab et al.       
                                                                  
      No modification was performed for JENDL-4.0.                
                                                                  
    Unresolved resonance region: 12.46 keV - 1 MeV                
      The parameters were obtained by fitting to the total and    
      capture cross sections calculated from POD /3/.  The        
      unresolved parameters should be used only for self-shielding
      calculation.                                                
                                                                  
    Thermal cross sections and resonance integrals at 300 K       
    ----------------------------------------------------------    
                     0.0253 eV           res. integ. (*)          
                      (barns)              (barns)                
    ----------------------------------------------------------    
     Total           4.5049E+00                                   
     Elastic         4.3849E+00                                   
     n,gamma         1.2004E-01           2.7200E+00              
    ----------------------------------------------------------    
       (*) Integrated from 0.5 eV to 10 MeV.                      
                                                                  
MF= 3 Neutron cross sections                                      
  MT=  1 Total cross section                                      
    Calculated with POD code /3/.                                 
                                                                  
  MT=  2 Elastic scattering cross section                         
    Obtained by subtracting non-elastic cross sections from total 
    cross sections.                                               
                                                                  
  MT=  3 Non-elastic cross section                                
    Sum of partial non-elastic cross sections.                    
                                                                  
  MT=  4,51-91 (n,n') cross section                               
    Calculated with POD code /3/.                                 
                                                                  
  MT= 16 (n,2n) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT= 17 (n,3n) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT= 22 (n,na) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT= 28 (n,np) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT= 32 (n,nd) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT=102 Capture cross section                                    
    Calculated with POD code /3/.                                 
                                                                  
  MT=103 (n,p) cross section                                      
    Calculated with POD code /3/.                                 
                                                                  
  MT=104 (n,d) cross section                                      
    Calculated with POD code /3/.                                 
                                                                  
  MT=105 (n,t) cross section                                      
    Calculated with POD code /3/.                                 
                                                                  
  MT=106 (n,He3) cross section                                    
    Calculated with POD code /3/.                                 
                                                                  
  MT=107 (n,a) cross section                                      
    Calculated with POD code /3/.                                 
                                                                  
  MT=203 (n,xp) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT=204 (n,xd) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT=205 (n,xt) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
  MT=206 (n,xHe3) cross section                                   
    Calculated with POD code /3/.                                 
                                                                  
  MT=207 (n,xa) cross section                                     
    Calculated with POD code /3/.                                 
                                                                  
MF= 4 Angular distributions of emitted neutrons                   
  MT=  2 Elastic scattering                                       
    Calculated with POD code /3/.                                 
                                                                  
MF= 6 Energy-angle distributions of emitted particles             
  MT= 16 (n,2n) reaction                                          
    Neutron spectra calculated with POD/3/.                       
                                                                  
  MT= 17 (n,3n) reaction                                          
    Neutron spectra calculated with POD/3/.                       
                                                                  
  MT= 22 (n,na) reaction                                          
    Neutron spectra calculated with POD/3/.                       
                                                                  
  MT= 28 (n,np) reaction                                          
    Neutron spectra calculated with POD/3/.                       
                                                                  
  MT= 32 (n,nd) reaction                                          
    Neutron spectra calculated with POD/3/.                       
                                                                  
  MT= 51 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 52 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 53 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 54 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 55 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 56 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 57 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 58 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 59 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 60 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 61 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 62 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 63 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 64 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 65 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 66 (n,n') reaction                                          
    Neutron angular distributions calculated with POD/3/.         
                                                                  
  MT= 91 (n,n') reaction                                          
    Neutron spectra calculated with POD/3/.                       
                                                                  
  MT= 203 (n,xp) reaction                                         
    Proton spectra calculated with POD/3/.                        
                                                                  
  MT= 204 (n,xd) reaction                                         
    Deuteron spectra calculated with POD/3/.                      
                                                                  
  MT= 205 (n,xt) reaction                                         
    Triton spectra calculated with POD/3/.                        
                                                                  
  MT= 206 (n,xHe3) reaction                                       
    He3 spectra calculated with POD/3/.                           
                                                                  
  MT= 207 (n,xa) reaction                                         
    Alpha spectra calculated with POD/3/.                         
                                                                  
MF=12 Gamma-ray multiplicities                                    
  MT=  3 Non-elastic gamma emission                               
    Calculated with POD code /3/.                                 
                                                                  
MF=14 Gamma-ray angular distributions                             
  MT=  3 Non-elastic gamma emission                               
    Assumed to be isotropic.                                      
                                                                  
MF=15 Gamma-ray spectra                                           
  MT=  3 Non-elastic gamma emission                               
    Calculated with POD code /3/.                                 
                                                                  
                                                        
                                                                  
***************************************************************   
*        Nuclear Model Calculations with POD Code /3/         *   
***************************************************************   
1. Theoretical models                                             
 The POD code is based on the spherical optical model, the        
distorted-wave Born approximaiton (DWBA), one-component exciton   
preequilibrium model, and the Hauser-Feshbach-Moldauer statis-    
tical model.  With the preequilibrim model, semi-empirical        
pickup and knockout process can be taken into account for         
composite-particle emission.  The gamma-ray emission from the     
compound nucleus can be calculated within the framework of the    
exciton model.  The code is capable of reading in particle        
transmission coefficients calculated by separate spherical or     
coupled-channel optical model code.                               
                                                                  
2. Optical model parameters                                       
Neutrons:                                                         
  Coupled-channel optical model parameters /4/                    
Protons:                                                          
  Koning and Delaroche /5/                                        
Deuterons:                                                        
  Lohr and Haeberli /6/                                           
Tritons:                                                          
  Becchetti and Greenlees /7/                                     
He-3:                                                             
  Becchetti and Greenlees /7/                                     
Alphas:                                                           
  Lemos /8/ potentials modified by Arthur and Young /9/           
                                                                  
3. Level scheme of Rb- 87                                         
  -------------------------                                       
   No.   Ex(MeV)     J  PI                                        
  -------------------------                                       
    0    0.00000    3/2  -                                        
    1    0.40259    5/2  -                                        
    2    0.84544    1/2  -                                        
    3    1.34938    7/2  +                                        
    4    1.38982    3/2  -                                        
    5    1.46300    1/2  -                                        
    6    1.57801    3/2  -                                        
    7    1.57810    9/2  +                                        
    8    1.74058    5/2  -                                        
    9    1.89300    1/2  -                                        
   10    1.95000    3/2  +                                        
   11    2.01300    5/2  -                                        
   12    2.28400    3/2  -                                        
   13    2.37841    5/2  +                                        
   14    2.37900    3/2  +                                        
   15    2.39700    1/2  -                                        
   16    2.41446    3/2  -                                        
  -------------------------                                       
  Levels above  2.42446 MeV are assumed to be continuous.         
                                                                  
4. Level density parameters                                       
 Energy-dependent parameters of Mengoni-Nakajima /10/ were used   
  ----------------------------------------------------------      
  Nuclei    a*    Pair    Esh     T     E0    Ematch Elv_max      
          1/MeV   MeV     MeV    MeV    MeV    MeV    MeV         
  ----------------------------------------------------------      
  Rb- 88  10.406  0.000 -0.431  0.771 -0.492  3.809  1.916        
  Rb- 87  10.932  1.287 -0.777  0.871 -0.070  6.722  2.414        
  Rb- 86   9.932  0.000  0.007  0.898 -1.348  5.547  1.738        
  Rb- 85  10.720  1.302  1.529  0.855 -0.855  7.650  2.088        
  Kr- 87  12.111  1.287 -0.112  0.649  0.793  4.518  3.172        
  Kr- 86  11.310  2.588 -0.507  0.715  2.085  6.130  3.575        
  Kr- 85  11.890  1.302  0.718  0.695  0.285  5.433  2.637        
  Br- 85  10.720  1.302 -0.138  0.819  0.183  6.155  1.944        
  Br- 84  11.060  0.000  0.608  0.898 -2.409  6.862  0.408        
  Br- 83  10.507  1.317  1.382  0.813 -0.276  6.734  2.134        
  ----------------------------------------------------------      
                                                                  
5. Gamma-ray strength functions                                   
   M1, E2: Standard Lorentzian (SLO)                              
   E1    : Generalized Lorentzian (GLO) /11/                      
                                                                  
6. Preequilibrium process                                         
   Preequilibrium is on for n, p, d, t, He-3, and alpha.          
   Preequilibrium capture is on.                                  
                                                                  
References                                                        
 1) M.Ohkubo et al, J. Nucl. Sci. Tech. 21, 254 (1984).           
 2) S.F.Mughabghab et al., "Neutron Cross Sections, Vol. I,       
    Part A", Academic Press (1981).                               
 3) A.Ichihara et al., JAEA-Data/Code 2007-012 (2007).            
 4) S.Kunieda et al., J. Nucl. Sci. Technol. 44, 838 (2007).      
 5) A.J.Koning, J.P.Delaroche, Nucl. Phys. A713, 231 (2003).      
 6) J.M.Lohr, W.Haeberli, Nucl. Phys. A232, 381 (1974).           
 7) F.D.Becchetti,Jr., G.W.Greenlees, "Polarization               
    Phenomena in Nuclear Reactions," p.682, The University        
    of Wisconsin Press (1971).                                    
 8) O.F.Lemos, Orsay Report, Series A, No.136 (1972).             
 9) E.D.Arthur, P.G.Young, LA-8626-MS (1980).                     
10) A.Mengoni, Y.Nakajima, J. Nucl. Sci. Technol. 31, 151         
    (1994).                                                       
11) J.Kopecky, M.Uhl, Nucl. Sci. Eng. 41, 1941 (1990).