56-Ba-136

 56-Ba-136 JNDC       EVAL-MAR90 JNDC FP NUCLEAR DATA W.G.        
                      DIST-MAY10                       20091217   
----JENDL-4.0         MATERIAL 5643                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
   ===========================================================    
   Resonance parameters in JENDL-3.3 were revised for JENDL-4.    
   ===========================================================    
                                                                  
   ===========================================================    
   JENDL-3.2 data were automatically transformed to JENDL-3.3.    
    Interpolation of spectra: 22 (unit base interpolation)        
    (3,251) deleted, T-matrix of (4,2) deleted, and others.       
   ===========================================================    
                                                                  
History                                                           
84-10 Evaluation for JENDL-2 was made by JNDC FPND W.G./1/        
90-03 Modification for JENDL-3 was made/2/.                       
                                                                  
10-03 JENDL-4.0 was made.                                         
      Resoloved resonance parameters were evaluated by K.Shibata. 
      Unresolved resonance parameters were evaluated by S.Kunieda.
      The LSSF=1 was applied.                                     
      Compiled by S.Kunieda                                       
                                                                  
      *****   modified parts for JENDL-4.0   ******************** 
        (1,451)   Updated.                                        
        (2,151)   Updated.                                        
        (3,1)     Re-calculated from partial cross sections.      
        (3,2)     Calculated from URP in lower energy range.      
        (3,4)     Re-calculated from partial cross sections.      
        (3,102)   Calculated from URP in lower energy range.      
      *********************************************************** 
                                                                  
                                                                  
mf = 1  General information                                       
  mt=451 Comments and dictionary                                  
                                                                  
mf = 2  Resonance parameters                                      
  mt=151 Resolved and unresolved resonance parameters             
  Resolved resonance parameters for MLBW formula (below 34.49 keV)
    The parameters are the same as JENDL-2 evaluated by Kikuchi et
    al./3/ on the basis of experimental data of Alves et al./4/,  
    Van de Vyver and Pattenden/5/ and Musgrove et al./6/  The     
    average radiation width of 0.125 eV/7/ was assumed.  Below 3  
    keV, 6 artificial levels were generated with stat/8/ by       
    assuming d = 225 eV, S0 = 0.8e-4/7/, S1 = 0.8e-4 and the      
    radiation width of 0.125 eV.  A negative resonance was added  
    by referring to Ref./7/ in order to reproduce the capture     
    cross section of 0.4 barns at 0.0253 eV/7/.                   
    ************************************************************* 
      Resolved resonance paramters were taken from the work of    
      Koehler et al./28/  A total spin J was determined by a      
      random number method.  A negative resonance was added so    
      as to reproduce the thermal capture cross section           
      recommended by Mughabghab./29/                              
    ************************************************************* 
                                                                  
  Unresolved resonance region : 34.49 keV - 100 keV               
    Unresolved resonance parameters were adopted from JENDL-2.    
    The neutron strength functions, S0, S1 and S2 were calculated 
    with optical model code CASTHY/9/.  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.                                                      
                                                                  
  Typical values of the parameters at 70 keV:                     
    S0 = 0.520e-4, S1 = 0.850e-4, S2 = 0.550e-4, Sg = 1.32e-4,    
    Gg = 0.112 eV, R  = 5.288 fm.                                 
                                                                  
   ***************************************************************
      For JENDL-4.0, the unresolved resonance parameters were     
    re-evaluated by the ASREP /30/ code so as to reproduce the    
    total and capture cross sections given in JENDL3.3 in the     
    energy region from 34.49 keV to 200 keV. The parameters       
    should be used only for self-shielding calculations.          
   ***************************************************************
                                                                  
     Thermal cross sections & resonance integrals at 300 K        
      ----------------------------------------------------------  
                       0.0253 eV           res. integ. (*)        
                        (barns)              (barns)              
      ----------------------------------------------------------  
       Total          3.44386E+00                                 
       Elastic        2.76338E+00                                 
       n,gamma        6.80477E-01           1.91575E+00           
      ----------------------------------------------------------  
      (*) Integrated from 0.5 eV to 10 MeV.                       
                                                                  
                                                                  
mf = 3  Neutron cross sections                                    
  Below 100 keV, resonance parameters were given.                 
  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/10/ standing on a preequilibrium and multi-step    
  evaporation model.  The OMP's for neutron given in Table 1 were 
  determined to reproduce a systematic trend of the total cross   
  section by changing Ws and rso of Iijima-Kawai potential/11/.   
  The OMP's for charged particles are as follows:                 
     proton   = Perey/12/                                         
     alpha    = Huizenga and Igo/13/                              
     deuteron = Lohr and Haeberli/14/                             
     helium-3 and triton = Becchetti and Greenlees/15/            
  Parameters for the composite level density formula of Gilbert   
  and Cameron/16/ were evaluated by Iijima et al./17/  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
  /18/.                                                           
                                                                  
  mt = 1  Total                                                   
    Spherical optical model calculation was adopted.              
                                                                  
  mt = 2  Elastic scattering                                      
    Calculated as (total - sum of partial cross sections).        
                                                                  
  mt = 4, 51 - 91  Inelastic scattering                           
    Spherical optical and statistical model calculation was       
    adopted.  The level scheme was taken from Ref./19/.           
                                                                  
           no.      energy(MeV)    spin-parity   dwba cal.        
           gr.       0.0             0  +                         
            1        0.8186          2  +            *            
            2        1.5505          2  +                         
            3        1.5792          0  +                         
            4        1.8663          4  +                         
            5        2.0540          4  +                         
            6        2.0799          2  +                         
            7        2.1280          2  +                         
            8        2.1402          5  -                         
            9        2.1415          0  +                         
           10        2.2071          6  +                         
      Levels above 2.284 MeV were assumed to be overlapping.      
                                                                  
    For the levels with an asterisk, the contribution of direct   
    inelastic scattering cross sections was calculated by the     
    DWUCK-4 code/20/.  Deformation parameter (beta2 = 0.1242) was 
    based on the data compiled by Raman et al./21/                
                                                                  
  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/22/ and normalized to 1 milli-barn at 14 MeV.       
                                                                  
    The gamma-ray strength function (1.22e-04) was adjusted to    
    reproduce the capture cross section of 45 milli-barns at 70   
    keV measured by Musgrove et al./23/                           
                                                                  
  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 =105  (n,t) cross section                                    
  mt =107  (n,alpha) cross section                                
    These reaction cross sections were calculated with the        
    preequilibrium and multi-step evaporation model code PEGASUS. 
                                                                  
    The Kalbach's constant k (= 257.1) was estimated by the       
    formula derived from Kikuchi-Kawai's formalism/24/ and level  
    density parameters.                                           
                                                                  
    Finally, the (n,2n), (n,p) and (n,alpha) cross sections were  
    normalized to the following values at 14.5 MeV:               
      (n,2n)      1670.00  mb (systematics of Wen Den Lu+/25/)    
      (n,p)          6.00  mb (measured by Ikeda+/26/)            
      (n,alpha)      2.04  mb (systematics of Forrest/27/)        
                                                                  
  mt = 251  mu-bar                                                
    Calculated with CASTHY.                                       
                                                                  
mf = 4  Angular distributions of secondary neutrons               
  Legendre polynomial coefficients for angular distributions are  
  given in the center-of-mass system for mt=2 and discrete inelas-
  tic levels, and in the laboratory system for mt=91.  They were  
  calculated with CASTHY.  Contribution of direct inelastic       
  scattering was calculated with DWUCK-4.  For other reactions,   
  isotropic distributions in the laboratory system were assumed.  
                                                                  
mf = 5  Energy distributions of secondary neutrons                
  Energy distributions of secondary neutrons were calculated with 
  PEGASUS for inelastic scattering from overlapping levels and for
  other neutron emitting reactions.                               
                                                                  
TABLE 1  NEUTRON OPTICAL POTENTIAL PARAMETERS                     
                                                                  
                DEPTH (MEV)       RADIUS(FM)    DIFFUSENESS(FM)   
         ----------------------   ------------  ---------------   
        V  = 41.8                 R0 = 6.89     A0 = 0.62         
        WS = 2.95+0.789E          RS = 7.098    AS = 0.35         
        VSO= 7.0                  RSO= 6.89     ASO= 0.62         
  THE FORM OF SURFACE ABSORPTION PART IS DER. WOODS-SAXON TYPE.   
                                                                  
TABLE 2  LEVEL DENSITY PARAMETERS                                 
                                                                  
 NUCLIDE       A(1/MEV)  T(MEV)    C(1/MEV)  EX(MEV)   PAIRING    
 ---------------------------------------------------------------  
 54-XE-132     1.563E+01 6.500E-01 5.485E-01 6.600E+00 2.160E+00  
 54-XE-133     1.600E+01 6.250E-01 2.327E+00 5.284E+00 1.120E+00  
 54-XE-134     1.400E+01 6.300E-01 3.184E-01 5.224E+00 1.820E+00  
 54-XE-135     1.550E+01 5.565E-01 7.506E-01 4.010E+00 1.120E+00  
                                                                  
 55-CS-133     1.750E+01 6.000E-01 3.784E+00 5.352E+00 1.040E+00  
 55-CS-134     1.598E+01 6.450E-01 1.710E+01 4.505E+00 0.0        
 55-CS-135     1.343E+01 6.537E-01 1.831E+00 4.203E+00 7.000E-01  
 55-CS-136     1.400E+01 6.000E-01 4.424E+00 2.967E+00 0.0        
                                                                  
 56-BA-134     1.800E+01 6.100E-01 4.177E-01 7.309E+00 2.620E+00  
 56-BA-135     1.902E+01 5.820E-01 2.277E+00 6.108E+00 1.580E+00  
 56-BA-136     1.610E+01 6.500E-01 5.721E-01 6.928E+00 2.280E+00  
 56-BA-137     1.645E+01 5.640E-01 5.394E-01 4.905E+00 1.580E+00  
 ---------------------------------------------------------------  
                                                                  
 Spin cutoff params were calculated as 0.146*sqrt(a)*a**(2/3).    
 In the CASTHY calculation, spin cutoff factors at 0 MeV were     
 assumed to be 6.925 for Ba-136 and 5.625 for Ba-137.             
                                                                  
References                                                        
 1) Aoki, T. et al.: Proc. Int. Conf. on Nuclear Data for Basic   
    and Applied Science, Santa Fe., Vol. 2, p.1627 (1985).        
 2) Kawai, M. et al.: Proc. Int. Conf. on Nuclear Data for Science
    and Technology, Mito, p. 569 (1988).                          
 3) Kikuchi, Y. et al.: JAERI-M 86-030 (1986).                    
 4) Alves, R.N., et al.: Nucl. Phys., A134, 118 (1969).           
 5) Van de Vyver, R.E., Pattenden, N.J.: Nucl. Phys., A177, 393   
    (1971).                                                       
 6) Musgrove, A.R. de L., et al.: Nucl. Phys., A256, 173 (1976).  
 7) Mughabghab, S.F. et al.: "Neutron Cross Sections, Vol. I,     
    Part A", Academic Press (1981).                               
 8) Kikuchi, Y.: JAERI-M 6248 (1975).                             
 9) Igarasi, S.: J. Nucl. Sci. Technol., 12, 67 (1975).           
10) Iijima, S. et al.: JAERI-M 87-025, p. 337 (1987).             
11) Iijima, S. and Kawai, M.: J. Nucl. Sci. Technol., 20, 77      
    (1983).                                                       
12) Perey, F.G: Phys. Rev. 131, 745 (1963).                       
13) Huizenga, J.R. and Igo, G.: Nucl. Phys. 29, 462 (1962).       
14) Lohr, J.M. and Haeberli, W.: Nucl. Phys. A232, 381 (1974).    
15) Becchetti, F.D., Jr. and Greenlees, G.W.: Polarization        
    Phenomena in Nuclear Reactions ((Eds) H.H. Barshall and       
    W. Haeberli), p. 682, the University of Wisconsin Press.      
    (1971).                                                       
16) Gilbert, A. and Cameron, A.G.W.: Can. J. Phys., 43, 1446      
    (1965).                                                       
17) Iijima, S., et al.: J. Nucl. Sci. Technol. 21, 10 (1984).     
18) Gruppelaar, H.: ECN-13 (1977).                                
19) Lederer, C.M., et al.: "Table of Isotopes, 7th Ed.", Wiley-   
    interscience Publication (1978).                              
20) Kunz, P.D.: private communication.                            
21) Raman, S., et al.: Atom. Data and Nucl. Data Tables 36, 1     
    (1987)                                                        
22) Benzi, V. and Reffo, G.: CCDN-NW/10 (1969).                   
23) Musgrove, A.R. de L., et al.: Proc. Int. Conf. on Neutron     
    Physics and Nucl. Data for Reactors, Harwell 1978, 449.       
24) Kikuchi, K. and Kawai, M.: "Nuclear Matter and Nuclear        
    Reactions", North Holland (1968).                             
25) Wen Den Lu and Fink, R.W.: Phys. Rev., C4, 1173 (1971).       
26) Ikeda, Y. et al.: JAERI 1312 (1988).                          
27) Forrest, R.A.: AERE-R 12419 (1986).                           
28) Koehler, P.E. et al.: Phys. Rev., C54, 1463 (1996).           
29) Mughabghab, S.F.: "Atlas of Neutron Resonances", Elsevier     
    (2006).                                                       
30) Y.Kikuchi et al., JAERI-Data/Code 99-025 (1999)               
    [in Japanese].