96-Cm-248

 96-CM-248 JAERI      EVAL-OCT95 T.NAKAGAWA AND T.LIU             
                      DIST-MAR02 REV2-OCT00            20001003   
----JENDL-3.3         MATERIAL 9649                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
                                                                  
HISTORY                                                           
84-03 EVALUATION FOR JENDL-3 WAS MADE BY Y.KIKUCHI AND            
      T.NAKAGAWA (JAERI).  DETAILS ARE GIVEN IN REF. /1/.         
95-10 NEW EVALUATION FOR JENDL ACTINIDE FILE WAS MADE BY          
      T.NAKAGAWA AND T.LIU.                                       
00-04 MODIFICATION WAS MADE BY T.NAKAGAWA.                        
                                                                  
     ***** Modified parts from JENDL-3.2 *******************      
     MF=2                                                         
     MF=3  All data                                               
     MF=4  All data                                               
     MF=5  All data                                               
     *******************************************************      
                                                                  
                                                                  
MF=1  GENERAL INFORMATION                                         
  MT=451   COMMENTS AND DICTIONARY                                
  MT=452   NUMBER OF NEUTRONS PER FISSION                         
             SUM OF MT'S =455 AND 456.                            
  MT=455   DELAYED NEUTRON DATA                                   
             SEMI-EMPIRICAL FORMULA BY TUTTLE /2/.                
  MT=456   PROMPT NEUTRON DATA                                    
             SEMI-EMPIRICAL FORMULA BY HOWERTON /3/.              
                                                                  
MF=2,MT=151  RESONANCE PARAMETERS                                 
        (TAKEN FROM JENDL-3.2)                                    
     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. THE FISSION    
        WIDTHS were adopted from Moore and Keyworth /5/ and       
        Maguire et al. /6/ THE AVERAGE FISSION WIDTH OF 0.0013    
        EV /5/ WAS USED FOR ALL RESONANCES OF WHICH FISSION       
        WIDTH HAD NOT BEEN MEASURED.  Then the fission widths were
        roughly adjusted to the fission cross section measured by 
        Maguire et al.  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              
        PARAMETERS WERE DETERMINED WITH A FITTING CODE ASREP/7/   
        OBTAINED FROM OPTICAL MODEL CALCULATION:                  
          S1=3.32E-4, S2=0.844E-4.                                
        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/     
        Scattring radius R was adjusted so as to reproduce the    
        ealstic scattering cross section calculated with CASTHY   
        at 30 keV.                                                
                                                                  
  CALCULATED 2200 M/S CROSS SECTIONS AND RESONANCE INTEGRALS      
                   2200 M/S VALUE           RES. INT.             
      TOTAL           9.456  B                 -                  
      ELASTIC         6.514  B                 -                  
      FISSION         0.372  B               10.0  B              
      CAPTURE         2.570  B              267.   B              
                                                                  
MF=3  NEUTRON CROSS SECTIONS                                      
     BELOW 30 KEV, CROSS SECTIONS WERE REPRESENTED WITH RESONANCE 
     PARAMETERS. BACKGROUND CROSS SECTION WAS GIVEN TO FISSION.   
                                                                  
  MT=1 TOTAL CROSS SECTION                                        
      CALCULATED WITH CASTHY CODE /8/ BASED ON THE SHERICAL       
      OPTICAL MODEL. THE OPTICAL POTENTIAL OF REF./9/ WERE        
      USED.                                                       
                                                                  
           V = 45.036-0.3*EN                        (MEV)         
           WS= 4.115+0.4*EN                         (MEV)         
           WV= 0             , VSO = 7.5            (MEV)         
           R = RSO = 1.256   , RS  = 1.260           (FM)         
           A = ASO = 0.626   , B   = 0.555+0.0045*EN (FM)         
                                                                  
      COMPETING PROCESSES OF THE FISSION, (N,2N) AND (N,3N) WERE  
      TAKEN INTO ACCOUNT.  THE FOLLOWING LEVEL DENSITY PARAMETERS 
      OF GILBERT-CAMERON'S FORMULA /10/ WERE USED.                
                                                                  
                 ISOTOPE        CM-248         CM-249             
                A(1/MEV)         27.8           34.2              
        SPIN-CUTOFF PARA.        30.39          33.79             
          PAIRING E(MEV)          0.0            0.903            
             TEMP. (MEV)          0.326          0.366            
                C(1/MEV)         10.8           12.2              
                 EX(MEV)          1.85           4.30             
                                                                  
      THE LEVEL SCHEME TAKEN FROM REF. /11/.                      
                   NO.        ENERGY(KEV)   SPIN-PARITY           
                  G.S.            0.0           0 +               
                   1.            43.4           2 +               
                   2.           143.8           4 +               
                   3.           298.8           6 +               
                   4.           506.0           8 +               
                   5.           761.9          10 +               
                   6.          1049.0           2 +               
                   7.          1049.0           1 -               
                   8.          1062.8          12 +               
                   9.          1084.0           0 +               
                  10.          1094.0           3 -               
                  11.          1126.0           2 +               
                  12.          1143.0           4 +               
                  13.          1172.0           5 -               
                  14.          1222.0           4 +               
                  15.          1235.0           3 -               
                  16.          1302.0           3 -               
                CONTINUUM LEVELS ASSUMED ABOVE 1314 KEV.          
                                                                  
  MT= 2         ELASTIC SCATTERING                                
      CALCULATED AS TOTAL - PARTIAL CROSS SECTIONS.               
                                                                  
  MT= 4         TOTAL INELASTIC SCATTERING                        
      SUM OF MT=51, 52, 53, 54 AND 91.                            
                                                                  
  MT=16,17      (N,2N),(N,3N)  CROSS SECTION                      
      STAPRE RESULTS CALCULATED BY KONSHIN /12/ WERE ADOPTED.     
                                                                  
  MT=18            FISSION CROSS SECTION                          
      BELOW 6 MEV TAKEN FROM JENDL-3.2 WHICH WAS EVALUATED ON     
      THE BASIS OF THE MEASURED DATA BY STOPA ET AL./6/ AND       
      FOMUSHKIN ET AL./13/. FROM 6 MEV TO 8 MEV, THE STAPRE       
      RESULT CALCULATED BY KONSHIN /12/ WERE USED.  FROM 8 MEV    
      TO 20 MEV BY EYE GUIDE, BASED ON THE MEASURED DATA OF       
      FOMUSHKIN ET AL./14/                                        
                                                                  
  MT=51, 52, 53, 54   Inelastic scattering                        
      CALCULATED BY ECIS /15/ AND CASTHY /8/ CODES.               
      LAGRANGE'S DEFORMED OPTICAL POTENTIAL PARAMETERS /16/ WERE  
      USED.                                                       
           V  = 49.82 - 17*((N-Z)/A) - 0.3*EN (MEV)               
           WS =  5.52 - 9*((N-Z)/A)+ 0.4*EN (MEV)