40-Zr- 90

 40-ZR- 90 JNDC       EVAL-AUG89 JNDC FP NUCLEAR DATA W.G.        
                      DIST-MAR02 REV4-FEB02            20020214   
----JENDL-3.3         MATERIAL 4025                               
-----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/.                       
90-10 mf=5: Spectra at threshold energies were modified.          
93-11 JENDL-3.2.                                                  
        Resonance parameters modified by M.Kawai(toshiba).        
        Other modifications were adopted from JENDL fusion file.  
      Compiled by t.nakagawa (ndc/jaeri)                          
                                                                  
     *****   modified parts for JENDL-3.2   ********************  
      (2,151)       Resolved resonance parameters                 
      (3,2), (3,4), (3,32), (3,51-57), (3,91)                     
                    Taken from JENDL fusion file                  
         (3,58-64): Deleted.                                      
      (4,16-91)     Taken from JENDL fusion file                  
      (5,16-91)     Taken from JENDL fusion file                  
     ***********************************************************  
01-08 Compiled by K.Shibata (jaeri/ndc) for JENDL-3.3.            
     *****   modified parts for JENDL-3.3   ********************  
      (1,451)       Updated.                                      
      (3,1)         Revised.                                      
      (3,2)         Re-calculated.                                
      (3,102)       Revised.                                      
      (3,251)       Deleted.                                      
      (3,203-207)   Calcualted.                                   
      (4,2)         Transformation matrix deleted.                
      (4,16-91)     Deleted.                                      
      (5,16-91)     Deleted.                                      
      (6,16-207)    Taken from JENDL fusion file.                 
      (12,16-107)   Added.                                        
      (14,16-107)   Added.                                        
      (15,16-107)   Added.                                        
     ***********************************************************  
02-01 Covariances were added by K.Shibata.                        
                                                                  
     -------------------------------------------------------------
      JENDL fusion file /3/  (as of Nov. 1993)                    
            Evaluated and comiled by S. Chiba (ndc/jaeri)         
                                                                  
      Data were taken from JENDL-3.1 except for the following:    
      -  The discrete and continuum inelastic scattering cross    
         sections were calculated with casthy2y and dwucky in     
         sincros-ii system/4/ including contributions from        
         direct reactions.                                        
      -  Angular distributions of discrete inelastics were also   
         calculated with casthy2y and dwucky.                     
      -  The (n,nd) reaction cross section (mt=32) was newly      
         calculated by egnash2 in the sincros-ii.                 
      -  All energy distributions of secondary neutrons were      
         replaced by those calculated by egnash2.  The ddx's of   
         the continuum neutrons were calculated by Kumabe's       
         systematics /5/ using f15tob /3/.  The precompound to    
         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/.  
     -------------------------------------------------------------
                                                                  
                                                                  
mf = 1  General information                                       
  mt=451 Comments and dictionary                                  
                                                                  
mf = 2  Resonance parameters                                      
  Resolved resonance region (MLBW formula) : below 171 keV        
       Resonance parameters for JENDL-3.1 were taken from JENDL-2 
    after slight modification.                                    
       For JENDL-2, resonance energies and neutron widths were    
    taken from the data of Musgrove et al./7/   Radiation widths  
    were derived from capture areas measured by Boldeman et al./8/
    The parameters of the first resonance were slightly adjusted  
    so as to reproduce the capture and and elastic scattering     
    cross sections at 0.0253 eV/9/.                               
      Average radiation width = 0.190 +- 0.110 eV for s-wave res, 
                                0.270 +- 0.120 eV for p-wave res, 
                                0.280 +- 0.120 eV for d-wave res. 
    The effective scattering radius of 7.0 fm was assumed.        
       For JENDL-3, the parameters of three d-wave resonances were
    modified and a negative resonance was added so as to reproduce
    the thermal capture cross section of 0.10+-0.07 barn measured 
    by Pomerance/10/, and the resonance integral given by         
    Mughabghab et al./9/                                          
       For JENDL-3.2, the parameters for the levels measured by   
    boldeman et al. in the energy range up to 192.9 keV were      
    reevaluated using their capture area data multiplied by 0.967 
    according to a corrigendum reported by Allen et al./11/.  The 
    negative resonance was removed because the positive resonance 
    parameters reproduce well the thermal cross sections/12/ and  
    resonance integral.                                           
                                                                  
  No unresolved resonance region                                  
                                                                  
  calculated 2200-m/s cross sections and res. integrals (barns)   
                     2200 m/s               res. integ.           
      total           5.376                    -                  
      elastic         5.365                    -                  
      capture         0.0112                   0.169              
                                                                  
mf = 3  Neutron cross sections                                    
  Below 171 keV, resonance parameters were given.                 
                                                                  
     In the evaluation for JENDL-3.1, above 171 keV, the spherical
  optical and statistical model calculation was performed with    
  casthy/13/, by taking account of competing reactions, of which  
  cross sections were calculated with pegasus/14/ standing on a   
  preequilibrium and multi-step evaporation model.  The omp's for 
  neutron given in Table 1 were determined by Iijima and Kawai/15/
  to reproduce a systematic trend of the total cross section.  The
  omp's for charged particles are as follows:                     
     proton   = Perey/16/                                         
     alpha    = Huizenga and Igo/17/                              
     deuteron = Lohr and Haeberli/18/                             
     helium-3 and triton = Becchetti and Greenlees/19/            
  Parameters for the composite level density formula of Gilbert   
  and Cameron/20/ were evaluated by Iijima et al./21/  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
  /22/.                                                           
                                                                  
     For JENDL-3.2, data of inelastic scattering and (n,nd) reac- 
  tion cross sections 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 neutrons, Lemos     
  omp modified by Arthur and Young/23/ for alpha, The same omp's  
  as the pegasus calculation for other charged particles and      
  standard level density parameters of sincros-ii system.         
                                                                  
  mt = 1  Total                                                   
    Spherical optical model calculation was adopted.              
    For JENDL-3.3, the cross sections was modified so as to       
    reproduce measured elemental data.                            
                                                                  
  mt = 2  elastic scattering                                      
    Calculated as (total - sum of partial cross sections).        
                                                                  
  mt = 4, 51 - 91  inelastic scattering                           
    Taken from JENDL fusion file.  The level scheme was taken from
    ref./6/  Contributions of the direct process was calculated   
    for the levels marked with '*'.                               
                                                                  
           no.      energy(MeV)    spin-parity (direct process)   
           gr.       0.0             0  +                         
            1        1.7607          0  +          *              
            2        2.1865          2  +          *              
            3        2.3191          5  -                         
            4        2.7388          4  -                         
            5        2.7479          3  -          *              
            6        3.0772          4  +          *              
            7        3.3087          2  +                         
      Levels above 3.309 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/24/ and normalized to 1 milli-barn at 14 MeV.       
                                                                  
    The gamma-ray strength function (1.41e-05) was adjusted to    
    reproduce the capture cross section of 7.5 milli-barns at 100 
    keV measured by Musgrove et al./25/                           
                                                                  
    For JENDL-3.3, the cross section was modified so as to        
    reproduce elemental data measured by Stavisskij et al./32/ and
    Poenitz/33/.                                                  
                                                                  
  mt = 16  (n,2n) 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 =106  (n,he3) cross section                                  
  mt =107  (n,alpha) cross section                                
  mt =111  (n,2p) cross section                                   
    These reaction cross sections were calculated with the        
    preequilibrium and multi-step evaporation model code pegasus. 
                                                                  
    The Kalbach's constant k (= 301.6) was estimated by the       
    formula derived from Kikuchi-Kawai's formalism/26/ and level  
    density parameters.                                           
                                                                  
    Finally, the (n,p) and (n,alpha) cross sections were          
    normalized to the following values at 14.5 MeV:               
      (n,p)         40.00  mb (recommended by Forrest/27/)        
      (n,alpha)     10.00  mb (recommended by Forrest)            
                                                                  
    The (n.2n) cross section was determined by eye-guiding to the 
    experimental data of Zhao Wen-Rong et al./28/, Pavlink et al. 
    /29/ and many measured data around 14.5 MeV.                  
                                                                  
  mt = 32  (n,n'd) cross section                                  
    Taken from JENDL fusion file.                                 
                                                                  
  mt=203   Total proton production                                
    Sum of mt=28, 103, and 2.0*mt=111.                            
                                                                  
  mt=204   Total deuteron production                              
    Sum of mt=32 and 104.                                         
                                                                  
  mt=205   Total triton production                                
    Equal to mt=105.                                              
                                                                  
  mt=206   Total He-3 production                                  
    Equal to mt=106.                                              
                                                                  
  mt=207   Total alpha production                                 
    Sum of mt=22 and 107.                                         
                                                                  
mf = 4  Angular distributions of secondary neutrons               
  mt = 2                                                          
    Calculated with casthy/13/.                                   
  mt = 51-57                                                      
    Taken from JENDL fusion file which was calculated with        
    casthy and dwuck/30/ (dwucky) in the sincros-ii system.       
                                                                  
mf = 6  Energy-angle distributions of secondary particles         
  mt = 16,22,28,32,91                                             
    Based on Kumabe's systematics/5/.                             
  mt = 203,204,205,206,207                                        
    Based on Kalbach's systematics/31/.                           
                                                                  
mf = 12  Photon production multiplicities                         
  mt=16, 22, 28, 91, 103, 107                                     
    Calculated with gnash code /4/.                               
  mt=102                                                          
    Calculated with casthy code /13/.                             
  mt=51-57                                                        
    Transitioin probability arrays                                
                                                                  
mf = 14  Photon angular distributions                             
  mt=16, 22, 28, 51-57, 91, 102, 103, 107                         
    Isotropic.                                                    
                                                                  
mf = 15  Continuous photon energy distributions                   
  mt=16, 22, 28, 91, 103, 107                                     
    Calculated with egnash code /4/.                              
  mt=102                                                          
    Calculated with casthy code /13/.                             
                                                                  
mf = 33  Covariances of cross sections                            
  mt=4                                                            
    Based on measured nonelastic and (n,2n) cross sections./34/   
  mt=16                                                           
    Based on measured cross sections./34/                         
  mt=102                                                          
    Based on experimental data./34/                               
                                                                  
                                                                  
                                                                  
================================================================= 
<> 
================================================================= 
                                                                  
Table 1  Neutron optical potential parameters                     
                                                                  
                depth (MeV)       radius(fm)    diffuseness(fm)   
         ----------------------   ------------  ---------------   
        V  = 46.0-0.25E           r0 = 5.893    a0 = 0.62         
        Ws = 7.0                  rs = 6.393    as = 0.35         
        Vso= 7.0                  rso= 5.893    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    
 ---------------------------------------------------------------  
 38-Sr- 86     1.120e+01 8.900e-01 5.328e-01 8.599e+00 2.700e+00  
 38-Sr- 87     1.030e+01 8.610e-01 1.186e+00 5.938e+00 1.240e+00  
 38-Sr- 88     9.160e+00 7.510e-01 8.288e-02 4.550e+00 2.170e+00  
 38-Sr- 89     9.380e+00 8.200e-01 5.043e-01 4.642e+00 1.240e+00  
                                                                  
 39-Y - 87  *  1.388e+01 7.471e-01 2.541e+00 6.730e+00 1.460e+00  
 39-Y - 88     1.109e+01 7.450e-01 3.738e+00 3.570e+00 0.0        
 39-Y - 89     7.900e+00 8.500e-01 3.983e-01 3.440e+00 9.300e-01  
 39-Y - 90     1.027e+01 6.770e-01 1.716e+00 2.209e+00 0.0        
                                                                  
 40-Zr- 88  *  1.404e+01 7.386e-01 4.932e-01 7.870e+00 2.660e+00  
 40-Zr- 89     1.095e+01 8.260e-01 1.379e+00 5.864e+00 1.200e+00  
 40-Zr- 90     9.152e+00 8.222e-01 1.526e-01 5.383e+00 2.130e+00  
 40-Zr- 91     1.036e+01 8.000e-01 7.822e-01 5.057e+00 1.200e+00  
 ---------------------------------------------------------------  
  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 10.12 for Zr- 90 and 12.04 for Zr- 91.             
                                                                  
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.: J. Nucl. Sci. Technol., 29, 195 (1992).     
 3) Chiba, S. et al.: JAERI-M 92-027, p.35 (1992).                
 4) Yamamuro, N.: JAERI-M 90-006 (1990).                          
 5) Kumabe, I. et al.: Nucl. Sci. Eng., 104, 280 (1990).          
 6) ENSDF: Evaluated Nuclear Structure Data File, BNL/NNDC.       
 7) Musgrove, A.R. de L. et al.: Aust. J. Phys., 30, 379 (1977).  
 8) Boldeman, J.W., et al.: Nucl. Phys., A246, 1 (1975).          
 9) Mughabghab, S.F. et al.: "Neutron Cross Sections, Vol. I,     
    Part A", Academic Press (1981).                               
10) Pomerance, H.: Phys. Rev., 88, 412 (1952).                    
11) Allen, B.J., et al.: Nucl. Sci. Eng., 82, 230 (1982).         
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    Grenoble, Sept.1981, p.383 (1981).                            
13) Igarasi, S. and Fukahori, T.: JAERI 1321 (1991).              
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    (1983).                                                       
16) Perey, F.G: Phys. Rev. 131, 745 (1963).                       
17) Huizenga, J.R. and Igo, G.: Nucl. Phys. 29, 462 (1962).       
18) Lohr, J.M. and Haeberli, W.: Nucl. Phys. A232, 381 (1974).    
19) 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).                                                       
20) Gilbert, A. and Cameron, A.G.W.: Can. J. Phys., 43, 1446      
    (1965).                                                       
21) Iijima, S., et al.: J. Nucl. Sci. Technol. 21, 10 (1984).     
22) Gruppelaar, H.: ECN-13 (1977).                                
23) Arthur, E.D. and Young, P.G.: LA-8626-MS (1980).              
24) Benzi, V. and Reffo, G.: CCDN-NW/10 (1969).                   
25) Musgrove, A.R. de L., et al.: Proc. Int. Conf. on Neutron     
    Physics and Nucl. Data for Reactors, Harwell 1978, 449.       
26) Kikuchi, K. and Kawai, M.: "Nuclear Matter and Nuclear        
    Reactions", North Holland (1968).                             
27) Forrest, R.A.: AERE-R 12419 (1986).                           
28) Zhao Wen-Rong, et al.: Chinese J. Nucl. Phys., 6, 80 (1984).  
29) Pavlink, A., et al.: J. Phys., G8, 1283 (1982).               
30) Kunz, P.D.: Private communication.                            
31) Kalbach, C. : Phys. Rev. C37, 2350(1988).                     
32) Stavisskij, Ju.Ja. et al.: At. Energija, 15, 323 (1963).      
33) Poenitz, W.P.: ANL-83-4, p.239 (1982).                        
34) Shibata K. et al.: JAERI-Research 96-041 (1996) [in Japanese].