96-Cm-248

 96-CM-248 JAERI      EVAL-MAR84 Y.KIKUCHI AND T.NAKAGAWA         
JAERI-M 84-116        DIST-SEP89                                  
----JENDL-3.2         MATERIAL 9649                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
HISTORY                                                           
84-03 NEW EVALUATION FOR JENDL-3 WAS MADE BY Y.KIKUCHI AND        
      T.NAKAGAWA (JAERI).  DETAILS ARE GIVEN IN REF. /1/.         
                                                                  
MF=1  GENERAL INFORMATION                                         
  MT=451  COMMENTS AND DICTIONARY                                 
  MT=452  NUMBER OF NEUTRONS PER FISSION                          
        SUM OF MT=455 AND MT=456.                                 
  MT=455  NUMBER OF DELAYED NEUTRONS PER FISSION                  
        SEMI-EMPIRICAL FORMULA BY TUTTLE /2/.                     
  MT=456  NUMBER OF NEUTRONS PER FISSION                          
        SEMI-EMPIRICAL FORMULA BY HOWERTON /3/.                   
                                                                  
MF=2  RESONANCE PARAMETERS                                        
  MT=151  RESONANCE PARAMETERS                                    
     RESOLVED RESONANCE REGION (MLBW) : 1.0E-5 TO 1.5 KEV         
        RESONANCE ENERGIES, NEUTRON AND RADIATIVE WIDTHS WERE     
        TAKEN FROM THE EXPERIMENTAL DATA OF BENJAMIN ET AL./4/.   
        FOR RESONANCES WHOSE RADIATIVE WIDTH WAS UNKNOWN, THE     
        AVERAGE VALUE OF 0.026 EV /4/ WAS ADOPTED.  FISSION WIDTHS
        AND THE AVERAGE FISSION WIDTH OF 0.0013 EV WERE ADOPTED   
        FROM MOORE AND KEYWORTH /5/.  THE AVERAGE FISSION WIDTH   
        WAS USED FOR ALL RESONANCES OF WHICH FISSION WIDTH HAD NOT
        BEEN MEASURED.  R=9.1 FM WAS ASSUMED TO REPRODUCE THE     
        POTENTIAL SCATTERING CROSS SECTION OF 10.4 BARNS ASSUMED  
        BY BENJAMIN ET AL./4/.  THE NEUTRON WIDTH OF THE FIRST    
        RESONANCE WAS SLIGHTLY ADJUSTED TO REPRODUCE THE CAPTURE  
        CROSS SECTION OF 2.57 BARNS AT 0.0253 EV.  BACKGROUND     
        CROSS SECTIONS WERE GIVEN ONLY FOR THE FISSION AND TOTAL  
        CROSS SECTIONS BY ASSUMING THE FORM OF 1/V.  THE THERMAL  
        CROSS SECTIONS TO BE REPRODUCED WERE ESTIMATED FROM       
        AVAILABLE EXPERIMENTAL DATA.                              
     UNRESOLVED RESONANCE REGION : 1.5 KEV TO 30 KEV              
        OBTAINED FROM OPTICAL MODEL CALCULATION:                  
          S1=3.32E-4, S2=0.844E-4, R=8.88 FM.                     
        ESTIMATED FROM RESOLVED RESONANCES:                       
          D-OBS=40.0 EV, GAM-G=26 MILLI-EV, S0=1.2E-4             
        GAM-F OBTAINED BY FITTING THE DATA OF STOPA ET AL./6/.    
                                                                  
  CALCULATED 2200 M/S CROSS SECTIONS AND RESONANCE INTEGRALS      
                   2200 M/S VALUE           RES. INT.             
      TOTAL           9.455  B                 -                  
      ELASTIC         6.514  B                 -                  
      FISSION         0.370  B               17.5  B              
      CAPTURE         2.570  B              260.   B              
                                                                  
MF=3  NEUTRON CROSS SECTIONS                                      
     BELOW 30 KEV, CROSS SECTIONS WERE REPRESENTED WITH RESONANCE 
     PARAMETERS.                                                  
                                                                  
  MT=1,2,4,51-58,91,102,251   TOTAL, ELASTIC AND INELASTIC        
     SCATTERING, CAPTURE CROSS SECTIONS AND MU-L                  
        CALCULATED WITH OPTICAL AND STATISTICAL MODEL CODE        
        CASTHY/7/.                                                
        THE SPHERICAL OPTICAL POTENTIAL PARAMETERS (MEV,FM):      
           V  =43.4-0.107*EN,              R  =1.282, A  =0.60    
           WS =6.95-0.339*EN+0.0531*EN**2, RS =1.29,  B  =0.50    
                (DERIVATIVE WOODS-SAXON FORM)                     
           VSO=7.0,                        RSO=1.282, ASO=0.60    
        THIS SET OF POTENTIAL PARAMETERS WAS DETERMINED /8/ TO    
        REPRODUCE WELL THE TOTAL CROSS SECTION OF AM-241 BY       
        PHILLIPS AND HOWE /9/.                                    
                                                                  
        IN THE STATISTICAL MODEL CALCULATION, COMPETING PROCESSES 
        OF FISSION, (N,2N), (N,3N) AND (N,4N), AND LEVEL          
        FLUCTUATION WERE CONSIDERED.  THE LEVEL SCHEME OF CM-248  
        WAS TAKEN FROM REF./10/.                                  
                   NO.        ENERGY(KEV)   SPIN-PARITY           
                  G.S.             0             0 +              
                    1             43.40          2 +              
                    2            143.6           4 +              
                    3            297             6 +              
                    4            510             8 +              
                    5           1048             2 +              
                    6           1050             1 -              
                    7           1084             0 +              
                    8           1094             3 -              
                CONTINUUM LEVELS ASSUMED ABOVE 1126 KEV.          
        THE LEVEL DENSITY PARAMETERS : GILBERT AND CAMERON /11/.  
        GAMMA-RAY STRENGTH FUNCTION OF 6.5E-4 DEDUCED FROM        
        RESONANCE PARAMETERS.                                     
                                                                  
  MT=16,17,37  (N,2N), (N,3N) AND (N,4N) REACTION CROSS SECTIONS  
        CALCULATED WITH EVAPORATION MODEL/12/.                    
                                                                  
  MT=18  FISSION                                                  
        EVALUATED ON THE BASIS OF THE MEASURED DATA BY STOPA ET   
        AL./6/ AND FOMUSHKIN ET AL./13/.                          
                                                                  
MF=4  ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS                 
  MT=2,51-58          CALCULATED WITH OPTICAL MODEL.              
  MT=16,17,18,37,91   ISOTROPIC IN THE LABORATORY SYSTEM.         
                                                                  
MF=5  ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS                  
  MT=16,17,37,91      EVAPORATION SPECTRUM.                       
  MT=18               MAXWELLIAN FISSION SPECTRUM.                
                      TEMPERATURE ESTIMATED FROM SYSTEMATICS OF   
                      SMITH ET AL./14/.                           
                                                                  
REFERENCES                                                        
 1) KIKUCHI Y. AND NAKAGAWA T.: JAERI-M 84-116 (1984).            
 2) TUTTLE R.J.: INDC(NDS)-107/G+SPECIAL, 29 (1979).              
 3) HOWERTON R.J.: NUCL. SCI. ENG., 62, 438(1977).                
 4) BENJAMIN R.W. ET AL.: NUCL. SCI. ENG., 55, 440(1974).         
 5) MOORE M.S. AND KEYWORTH G.A.: PHYS. REV., C3, 1656(1971)      
 6) STOPA C.R.S. ET AL.: 1982 KIAMESHA, 1090 (1982), AND          
    MAGUIRE JR. H.T. ET AL.: NUCL. SCI. ENG., 89, 293 (1985).     
 7) IGARASI S.: J. NUCL. SCI. TECHNOL., 12, 67 (1975).            
 8) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).              
 9) PHILLIPS T.W. AND HOWE F.R.: NUCL. SCI. ENG., 69, 375(1979).  
10) LEDERER C.M. AND SHIRLEY V.S.: TABLE OF ISOTOPES , 7TH ED.    
    (1978).                                                       
11) GILBERT A. AND CAMERON A.G.W.: CAN. J. PHYS., 43, 1446(1965). 
12) PEARLSTEIN S.: NUCL. SCI. ENG., 23, 238 (1965).               
13) FOMUSHKIN E.F. ET AL.: SOV. J. NUCL. PHYS., 31, 19(1980).     
14) SMITH A.B. ET AL.: ANL/NDM-50 (1979).