99-Es-254

 99-ES-254 TIT        EVAL-AUG87 N.TAKAGI                         
                      DIST-SEP89 REV2-JUN94                       
----JENDL-3.2         MATERIAL 9914                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
HISTORY                                                           
87-08 NEW EVALUATION WAS MADE BY N. TAKAGI (TOKYO INSTITUTE OF    
      TECHNOLOGY, TIT) /1/.                                       
94-06 JENDL-3.2.                                                  
       NU-P, NU-D AND NU-TOTAL WERE MODIFIED.                     
      COMPILED BY T.NAKAGAWA (NDC/JAERI)                          
                                                                  
     *****   MODIFIED PARTS FOR JENDL-3.2   ********************  
      (1,452), (1,455), (1,456)                                   
     ***********************************************************  
                                                                  
                                                                  
MF=1  GENERAL INFORMATION                                         
  MT=451   COMMENT AND DICTIONARY                                 
  MT=452   NUMBER OF NEUTRONS PER FISSION                         
        SUM OF NU-P NAD NU-D.                                     
  MT=455   DELAYED NEUTRONS PER FISSION                           
        AVERAGE VALUES OF SYSTEMATICS BY TUTTLE/2/, BENEDETTI ET  
        AL./3/ AND WALDO ET AL./4/  DECAY CONSTANTS WERE EVALUATED
        BY BRADY AND ENGLAND/5/.                                  
  MT=456   PROMPT NEUTRONS PER FISSION                            
        CALCULATED FROM THE SEMI-EMPIRICAL FORMULA OF HOWERTON/6/.
                                                                  
MF=2  RESONANCE PARAMETERS                                        
  MT=151   RESONANCE PARAMETERS                                   
    NO RESONANCE PARAMETERS WERE GIVEN.                           
                                                                  
  2200-M/S CROSS SECTIONS AND RESONANCE INTEGRALS                 
                      2200 M/S VALUE       RES. INT.              
        TOTAL          2004.90  B            -                    
        ELASTIC          10.60  B            -                    
        FISSION        1966.00  B           1220   B              
        CAPTURE          28.30  B            18.0  B              
                                                                  
MF=3  NEUTRON CROSS SECTIONS                                      
  MT=1  TOTAL CROSS SECTION                                       
        BELOW 5 EV, CALCULATED AS SUM OF MT'S = 2, 18 AND 102.    
        ABOVE 5 EV, OPTICAL MODEL CALCULATION WAS MADE WITH       
        CASTHY/7/.  THE POTENTIAL PARAMETERS/8/ USED ARE AS       
        FOLLOWS,                                                  
           V = 43.4 - 0.107*EN                      (MEV)         
           WS= 6.95 - 0.339*EN + 0.0531*EN**2       (MEV)         
           WV= 0             , VSO = 7.0            (MEV)         
           R = RSO = 1.282   , RS = 1.29            (FM)          
           A = ASO = 0.60    , B  = 0.5             (FM)          
                                                                  
  MT=2  ELASTIC SCATTERING CROSS SECTION                          
        BELOW 5 EV, THE CONSTANT CROSS SECTION OF 10.6 BARNS WAS  
        ASSUMED, WHICH WAS THE SHAPE ELASTIC SCATTERING CROSS     
        SECTION CALCULATED WITH OPTICAL MODEL.  ABOVE THIS ENERGY,
        OPTICAL MODEL CALCULATION WAS ADOPTED.                    
                                                                  
  MT=4,51-52,91  INELASTIC SCATTERING CROSS SECTIONS.             
        OPTICAL AND STATISTICAL MODEL CALCULATION WAS MADE WITH   
        CASTHY/7/.  THE LEVEL SCHEME WAS TAKEN FROM REF./9/.      
                   NO         ENERGY(KEV)   SPIN-PARITY           
                  G.S.             0.0          7 +               
                    1             78.0          2 +               
        LEVELS ABOVE 503 KEV WERE ASSUMED TO BE OVERLAPPING.      
        THE LEVEL DENSITY PARAMETERS WERE TAKEN FROM REF./10/.    
                                                                  
  MT=16,17,37  (N,2N), (N,3N) AND (N,4N) REACTION CROSS SECTIONS  
        CALCULATED WITH EVAPORATION MODEL.                        
                                                                  
  MT=18  FISSION CROSS SECTION                                    
        MEASURED THERMAL CROSS SECTION OF 1966 BARNS WAS TAKEN    
        FROM REF./11/. THE 1/V FORM WAS ASSUMED BELOW 5 EV. THE   
        SHAPE OF CROSS SECTION NEAR 5 EV WAS ADJUSTED SO AS TO    
        REPRODUCE THE MEASURED RESONANCE INTEGRAL OF 1200+-250    
        BARNS/11/.  ABOVE 5 EV, THE CROSS SECTION SHAPE WAS       
        ASSUMED TO BE THE SAME AS BK-250 FISSION CROSS SECTION    
        AND IT WAS NORMALIZED TO SYSTEMATICS OF BEHRENS AND       
        HOWERTON/12/.                                             
                                                                  
  MT=102  CAPTURE CROSS SECTION                                   
        MEASURED THERMAL CROSS SECTION OF 28.3 BARNS WAS TAKEN    
        FROM REF./11/, AND 1/V FORM WAS ASSUMED BELOW 5 EV.  THE  
        CROSS SECTION NEAR 5 EV WAS ADJUSTED SO AS TO REPRODUCE   
        THE MEASURED RESONANCE INTEGRAL OF 18.2+-1.5 BARNS/11/.   
        ABOVE 5 EV, CALCULATED WITH CASTHY. THE GAMMA-RAY STRENGTH
        FUNCTION WAS ESTIMATED FROM GAMMA-GAMMA = 0.040 EV AND    
        LEVEL SPACING = 2 EV.                                     
                                                                  
  MT=251  MU-L                                                    
        CALCULATED WITH CASTHY.                                   
                                                                  
MF=4  ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS                 
  MT=2,51-52,91       CALCULATED WITH OPTICAL MODEL.              
  MT=16,17,18,37      ISOTROPIC IN THE LAB SYSTEM.                
                                                                  
MF=5  ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS                  
  MT=16,17,37,91      EVAPORATION SPECTRA                         
         OBTAINED FROM LEVEL DENSITY PARAMETERS.                  
                                                                  
  MT=18               MAXWELLIAN FISSION SPECTRUM.                
        TEMPERATURE WAS ESTIMATED FROM Z**2/A DEPENDENCE/13/.     
                                                                  
REFERENCES                                                        
 1) TAKAGI N. ET AL.: J. NUCL. SCI. TECHNOL., 27, 853 (1990).     
 2) TUTTLE R.J.: INDC(NDS)-107/G+SPECIAL, P.29 (1979),            
 3) BENEDETTI G. ET AL.: NUCL. SCI. ENG., 80, 379 (1982).         
 4) WALDO R. ET AL.: PHYS. REV., C23, 1113 (1981).                
 5) BRADY M.C. AND ENGLAND T.R.: NUCL. SCI. ENG., 103, 129 (1989).
 6) HOWERTON R.J.: NUCL. SCI. ENG., 62, 438 (1977).               
 7) IGARASI S. AND FUKAHORI T.: JAERI 1321(1991).                 
 8) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).              
 9) SCHMORAK M.R.: NUCL. DATA SHEETS, 32, 87 (1981).              
10) GILBERT A. AND CAMERON A.G.W.: CAN. J. PHYS., 43, 1446 (1965).
11) MUGHABGHAB S.F.: "NEUTRON CROSS SECTIONS, VOL.1, NEUTRON      
    RESONANCE PARAMETERS AND THERMAL CROSS SECTIONS , PART B,     
    Z=61-100", ACADEMIC PRESS (1984).                             
12) BEHRENS J.W. AND HOWERTON R.J: NUCL. SCI. ENG., 65, 464       
    (1978).                                                       
13) SMITH A.B. ET AL.: ANL/NDM-50 (1979).