92-U -237

 92-U -237 JAERI      EVAL-MAR93 T.NAKAGAWA                       
                      DIST-MAR02 REV2-FEB02            20020222   
----JENDL-3.3         MATERIAL 9234                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
   ===========================================================    
   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                                                           
93-03  NEW EVALUATION WAS MADE FOR JENDL-3.2.                     
                                                                  
MF=1  GENERAL INFORMATION                                         
  MT=451  DESCRIPTIVE DATA AND DICTIONARY                         
  MT=452  TOTAL NUMBER OF NEUTRONS PER FISSION                    
      SUM OF NU-P (MT=456) AND NU-D (MT=455).                     
  MT=455  DELAYED NEUTRON DATA                                    
      DETERMINED FROM SYSTEMATICS BY TUTTLE/1/, BENEDETTI/2/ AND  
      WALDO ET AL./3/  DECAY CONSTANTS WERE TAKEN FROM THE EVALU- 
      ATION OF BRADY AND ENGLAND/4/.                              
  MT=456  NUMBER OF PROMPT NEUTRONS                               
      HOWERTON'S SYSTEMATICS/5/.                                  
                                                                  
MF=2  RESONANCE PARAMETERS                                        
  MT=151                                                          
   1) RESOLVED RESONANCE PARAMETERS: MLBW (1.0E-5 - 200 EV)       
      BELOW 45 EV, HYPOTHETICAL RESONANCES WERE GENERATED FROM    
      FISSION WIDTH OF 0.004 EV, S0 OF 1.0E-4 AND LEVEL SPACING OF
      3.5 EV, AND ADJUSTED TO REPRODUCE THERMAL CROSS SECTIONS.   
      ABOVE 46 EV, PARAMETERS WERE ESTIMATED FROM FISSION-AREA    
      DATA MEASURED BY MCNALLY ET AL./6/                          
   2) UNRESOLVED RESONANCE PARAMETERS: 200 EV - 30 KEV            
      OBTAINED BY FITTING TO CAPTURE AND FISSION CROSS SECTIONS   
      WITH ASREP/7/.                                              
         S0 AND S2 = (0.97 - 1.02)E-4, S1 = (1.95 - 2.04)E-4,     
         GAMMA-F = (0.006 - 0.070) EV, GAMMA-G = 0.035 EV         
         R = 9.668 FM                                             
                                                                  
      CALCULATED THERMAL CROSS SECTIONS AND RES. INTEGRAL (BARNS) 
                     0.0253 EV      RESONANCE INTEGRAL            
        TOTAL         478.5                -                      
        ELASTIC        24.39               -                      
        FISSION         1.70             48.7                     
        CAPTURE       452.4            1080                       
                                                                  
MF=3  NEUTRON CROSS SECTIONS                                      
      BELOW 200 EV, CROSS SECTIONS WERE REPRESENTED WITH RESOLVED 
      RESONANCE PARAMETERS. ABOVE 200 EV, THEY WERE EVALUATED AS  
      FOLLOWS, AND THE UNRESOLVED RESONANCE PARAMETERS WERE GIVEN 
      SO AS TO REPRODUCE THE CROSS SECTIONS IN THE ENERGY RANGE   
      FROM 200 EV TO 30 KEV.                                      
                                                                  
  MT= 1    TOTAL CROSS SECTION                                    
      CALCULATED FROM THE OPTICAL MODEL WITH CASTHY/8/.           
      PARAMETERS ARE LISTED IN TABLE 1.                           
                                                                  
  MT= 2    ELASTIC SCATTERING CROSS SECTION                       
      TOTAL - SUM OF PARTIAL CROSS SECTIONS                       
                                                                  
  MT= 16, 17  (N,2N) AND (N,3N) CROSS SECTIONS                    
      CALCULATED FROM A FORMULA GIVEN BY SAGEV AND CANER/9/.      
      THE REACTION CROSS SECTIONS CALCULATED WITH CASTHY WAS      
      ADOPTED AS THE NON-ELASTIC SCATTERING CROSS SECTION.        
                                                                  
  MT= 18   FISSION CROSS SECTION                                  
      CROSS SECTION OF 2.5 B AT 200 EV WAS ASSUMED FROM THE DATA  
      OF MCNALLY ET AL./6/  CROSS SECTION AT 100 KEV WAS ASSUMED  
      TO BE 0.6 B.  ABOVE 5 MEV, A SIMPLE FORMULA BY BYCHKOV ET   
      AL./9/ WAS USED.  EXPERIMENTAL DATA OF CRAMER AND BRITT/10/ 
      AND SYSTEMATICS/11/ WERE ALSO CONSIDERED.                   
                                                                  
  MT= 4, 51-79, 91  INELASTIC SCATTERING CROSS SECTION            
      CALCULATED WITH CASTHY (OPTICAL AND STATISTICAL MODEL).     
      PARAMETERS USED ARE LISTED IN TABLES 1, 2 AND 3.  THE LEVEL 
      SCHEME WAS TAKEN FROM EVALUATION BY ELLIS-AKOVALI/12,13/.   
                                                                  
  MT= 102  CAPTURE CROSS SECTION                                  
      CALCULATED WITH CASTHY.  AVERAGE CAPTURE WIDTH AND LEVEL    
      SPACING WAS ASSUMED TO BE 0.035 EV AND 3.5 EV, RESPECTIVELY.
      DIRECT AND SEMI-DIRECT CAPTURE WAS CALCULATED FROM A SIMPLE 
      FORMULA OF BENZI AND REFFO/14/.                             
                                                                  
  MT= 251  MU-L                                                   
      CALCULATED WITH CASTHY                                      
                                                                  
MF=4  ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS                 
  MT= 2, 51-79, 91                                                
      CALCULATED WITH CASTHY                                      
                                                                  
  MT=16, 17, 18                                                   
      ASSUMED TO BE ISOTROPIC IN THE LABORATORY SYSTEM.           
                                                                  
MF=5  ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS                  
  MT=16, 17, 91                                                   
      EVAPORATION SPECTRA OBTAINED FROM THE LEVEL DENSITY         
      PARAMETERS WERE GIVEN.                                      
  MT=18                                                           
      EVAPORATION SPECTRA.  TEMPERATURE WAS DETERMINED FROM       
      SYSTEMATICS BY SMITH ET AL./15/                             
                                                                  
    TABLE 1   OPTICAL POTENTIAL PARAMETERS                        
              DETERMINED BY MURATA/16/ EXCEPT A CONSTANT TERM OF V
              THAT WAS SELECTED SO AS TO REPRODUCE S0 OF 1.0E-4.  
    ------------------------------------------------------------- 
         V = 40.5 - 0.05*E (MEV)                                  
        WS =  6.5 + 0.15*E (MEV): DERRIVATIVE WOOD-SAXON TYPE     
       VSO =  7.0          (MEV)                                  
        R0 = RSO = 1.32,  RS = 1.38  (FM)                         
         A = B = ASO = 0.47          (FM)                         
    ------------------------------------------------------------- 
                                                                  
    TABLE 2  LEVEL SCHEME OF U-237 /12,13/                        
    ------------------------------------------------------------- 
        NO.  ENERGY(MEV)  SPIN-PARITY                             
    ------------------------------------------------------------- 
        G.S   0.0           1/2 +                                 
         1    0.01139       3/2 +                                 
         2    0.05630       5/2 +                                 
         3    0.08286       7/2 +                                 
         4    0.15996       5/2 +                                 
         5    0.20419       7/2 +                                 
         6    0.2740        7/2 -                                 
         7    0.3160        9/2 -                                 
         8    0.42615       7/2 +                                 
         9    0.4820        9/2 +                                 
        10    0.54062       1/2 -                                 
        11    0.55498       3/2 -                                 
        12    0.57801       5/2 -                                 
        13    0.66427       3/2 +                                 
        14    0.66645       5/2 +                                 
        15    0.67759       3/2 +                                 
        16    0.69765       5/2 +                                 
        17    0.72045       3/2 -                                 
        18    0.73434       1/2 -                                 
        19    0.75816       3/2 -                                 
        20    0.83245       5/2 +                                 
        21    0.84694       1/2 +                                 
        22    0.8650        1/2 -                                 
        23    0.87215       3/2 +                                 
        24    0.89343       5/2 +                                 
        25    0.9034        3/2 -                                 
        26    0.9057        1/2 +                                 
        27    0.9094        1/2 -                                 
        28    0.9110        5/2 -                                 
        29    0.9206        3/2 +                                 
    ------------------------------------------------------------- 
          LEVELS ABOVE 0.94785 MEV WERE ASSUMED TO BE OVERLAPPING.
                                                                  
    TABLE 3  LEVEL DENSITY PARAMETERS FOR GILBERT AND CAMERON     
             FORMULA, BASED ON THE EXCITED LEVELS GIVEN IN ENSDF  
             AND RESONANCE LEVEL SPACINGS /17/.                   
                                                                  
    ------------------------------------------------------------- 
                              PAIRING    SPIN-CUTOFF F.           
             A(1/MEV) T(MEV) ENERGY(MEV)   (MEV**0.5)    EX(MEV)  
    ------------------------------------------------------------- 
       U-235   31.4    0.39    0.69         31.55        4.1984   
       U-236   30.42   0.39    1.18         30.752       4.5349   
       U-237   31.6    0.37    0.69         31.431       3.807    
       U-238   30.1    0.38    1.12         30.762       4.227    
    ------------------------------------------------------------- 
                                                                  
REFERENCES                                                        
 1) R.J.TUTTLE: INDC(NDS)-107/G+SPECIAL, P.29 (1979).             
 2) G.BENEDETTI, ET AL.: NUCL. SCI. ENG., 80, 379 (1982).         
 3) R.WALDO ET AL.: PHYS. REV., C23, 1113 (1981).                 
 4) M.C.BRADY AND T.R.ENGLAND: NUCL. SCI. ENG., 103, 129 (1989).  
 5) R.J.HOWERTON: NUCL. SCI. ENG., 62, 438 (1977).                
 6) J.H.MCNALLY ET AL: PHYS. REV., C9, 717 (1974).                
 7) Y.KIKUCHI: UNPUBLISHED.                                       
 8) S.IGARASI AND T.FUKAHORI: JAERI 1321 (1991).                  
 9) V.M.BYCHKOV ET AL.: INDC(CCP)-184/L (1982).                   
10) J.D.CRAMER AND H.C.BRITT: NUCL. SCI. ENG., 41, 177 (1970).    
11) J.W.BEHRENS AND R.J.HOWERTON: NUCL. SCI. ENG., 65, 464 (1978).
12) Y.A.ELLIS-AKOVALI: NUCLEAR DATA SHEETS, 49, 181 (1986).       
13) ENSDF: EVALUATED NUCLEAR STRUCTURE DATA FILE, BNL/NNDC, AS OF 
    JAN. 1993.                                                    
14) V.BENZI AND G.REFFO: CCDN-NW/10 (1969).                       
15) A.B.SMITH ET AL.: ANL/NDM-50 (1979).                          
16) H.MATSUNOBU ET AL.: PROC. IN. CONF. ON NUCLEAR CROSS SECTIONS 
    FOR TECHNOL., KNOXVILLE, 1979, P.715 (1980).                  
17) S.F.MUGHABGHAB: NEUTRON CROSS SECTIONS, VOL.1, PART A,        
    ACADEMIC PRESS (1984).