96-Cm-243

 96-CM-243 JAERI      EVAL-MAR89 T.NAKAGAWA                       
                      DIST-SEP89                                  
----JENDL-3.2         MATERIAL 9634                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
HISTORY                                                           
81-03 EVALUATION FOR JENDL-2 WAS MADE BY T.NAKAGAWA AND S.IGARASI 
      (JAERI) /1/.                                                
89-03 RE-EVALUATION FOR JENDL-3 WAS MADE BY T.NAKAGAWA (JAERI)/2/.
                                                                  
MF=1  GENERAL INFORMATION                                         
  MT=451  DESCRIPTIVE DATA                                        
  MT=452  NUMBER OF NEUTRONS PER FISSION                          
        SUM OF MT=455 AND MT=456.                                 
  MT=455  DELAYED NEUTRON DATA                                    
        ESTIMATED FROM THE SYSTEMATICS BY TUTTLE /3/.             
  MT=456  NUMBER OF PROMPT NEUTRONS PER FISSION                   
        BASED ON THE EXPERIMENTAL DATA AT THERMAL ENERGY BY JAFFEY
        AND LERNER /4/, AND ZHURAVLEV ET AL. /5/, AND ON THE      
        EMPIRICAL FORMULA BY HOWERTON /6/.                        
                                                                  
MF=2  RESONANCE PARAMETERS                                        
  MT=151  RESONANCE PARAMETERS                                    
     RESOLVED RESONANCE REGION (SLBW): 1.0E-5 EV TO 70 EV.        
          RESONANCE ENERGIES = ANUFRIEV ET AL. /7/                
          NEUTRON WIDTHS     = ANUFRIEV ET AL. /7/ (ASSUMING 2G=1)
          RADIATIVE WIDTHS   = 0.040 EV (ASSUMED)                 
          FISSION WIDTHS     = TOTAL WIDTH /7/ - (WN+WG)          
          SCATTERING RADIUS  = 10 FM.                             
        A NEGATIVE RESONANCE WAS ADOPTED SO AS TO REPRODUCE WELL  
        THE THERMAL CROSS SECTIONS/8/.                            
     UNRESOLVED RESONANCE PARAMETERS : 70 EV - 40 KEV             
        PARAMETERS WERE DETERMINED WITH A FITTING CODE ASREP/9/ SO
        AS TO REPRODUCE THE FISSION CROSS SECTION BASED ON SILBERT
        /10/, AND THE TOTAL CROSS SECTION CALCULATED WITH OPTICAL 
        MODEL.                                                    
          ENERGY INDEPENDENT PARAMETERS:                          
            R=9.810 FM, S2=1.70E-4, WG=0.04 EV, WF=1.481 EV       
          ENERGY DEPENDENT PARAMETERS AT 1 KEV:                   
            S0=1.32E-4, S1=1.06E-4, D=0.799 EV.                   
                                                                  
      CALCULATED 2200M/S CROSS SECTIONS AND RESONANCE INTEGRALS.  
                           2200 M/SEC    RES. INTEG.              
              TOTAL         757.5  B        -                     
              ELASTIC         9.926 B       -                     
              FISSION       617.4  B      1560 B                  
              CAPTURE       130.2  B       199 B                  
                                                                  
MF=3  NEUTRON CROSS SECTIONS                                      
     BELOW 40 KEV, CROSS SECTIONS WERE REPRESENTED WITH RESONANCE 
     PARAMETERS.                                                  
                                                                  
  MT=1,2,4,51-63,91,102,251   TOTAL, ELASTIC AND INELASTIC        
     SCATTERING, CAPTURE CROSS SECTIONS AND MU-L                  
        CALCULATED WITH OPTICAL AND STATISTICAL MODEL CODE        
        CASTHY/11/.                                               
        THE SPHERICAL OPTICAL POTENTIAL PARAMETERS (MEV,FM):      
           V  =41.0-0.107*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 /12/ TO   
        REPRODUCE WELL THE TOTAL CROSS SECTION OF AM-241 BY       
        PHILLIPS AND HOWE /13/, AND A REAL PART WAS MODIFIED A    
        LITTLE TO GIVE A SLIGHTLY LARGE STRENGTH FUNCTION IN A LOW
        ENERGY REGION.                                            
                                                                  
        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-243  
        WAS TAKEN FROM THE COMPILATION BY ELLIS-AKOVALI /14/:     
              NO.     ENERGY(MEV)        SPIN-PARITY              
             G.S.       0.0               5/2  +                  
               1        0.042             7/2  +                  
               2        0.0874            1/2  +                  
               3        0.094             9/2  +                  
               4        0.094             3/2  +                  
               5        0.133             7/2  +                  
               6        0.153            11/2  +                  
               7        0.164             9/2  +                  
               8        0.219            13/2  +                  
               9        0.228            11/2  +                  
              10        0.260             9/2  +                  
              11        0.530            15/2  -                  
              12        0.729             1/2  -                  
              13        0.769             3/2  -                  
        OVERLAPPING LEVELS ARE ASSUMED ABOVE 0.82 MEV.  THE LEVEL 
        DENSITY PARAMETERS WERE DETERMINED ON THE BASIS OF NUMBERS
        OF EXCITED LEVELS/15/ AND RESONANCE LEVEL SPACING/8/.     
                                 CM-244    CM-243                 
                      A(1/MEV)    28.0      28.0                  
                        T(MEV)    0.395     0.40                  
                      C(1/MEV)    1.8807    7.5405                
                      E-X(MEV)    4.2893    3.8863                
       SPIN-CUTOFF(1/MEV**0.5)    30.17     30.08                 
                PAIRING E(MEV)    1.22      0.72                  
                                                                  
        AVERAGE RADIATIVE WIDTH = 0.040 EV AND D = 0.809 EV /7/   
        WERE USED FOR THE CAPTURE CROSS SECTION CALCULATION.      
                                                                  
  MT=16,17,37  (N,2N),(N,3N) AND (N,4N) CROSS SECTIONS            
        CALCULATED WITH THE EVAPORATION MODEL BY PEARLSTEIN/16/.  
        NEUTRON EMISSION CROSS SECTION WAS ASSUMED TO BE (COMPOUND
        NUCLEUS FORMATION CROSS SECTION CALCULATED WITH OPTICAL   
        MODEL - FISSION).                                         
                                                                  
  MT=18 FISSION CROSS SECTION                                     
        BELOW 10 KEV  : TAKEN FROM JENDL-2 EVALUATION BASED ON    
                        SILBERT /10/.                             
        10 KEV - 3 MEV: DETERMINED FROM FOMUSHKIN ET AL. /17/.    
        ABOVE 3 MEV   : ESTIMATED.                                
                                                                  
MF=4  ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS                 
  MT=2,51-63,91                                                   
        LEGENDRE COEFFICIENTS CALCULATED WITH CASTHY /11/.        
  MT=16,17,18,37                                                  
        ISOTROPIC DISTRIBUTIONS IN THE LABORATORY SYSTEM.         
                                                                  
MF=5  ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS                  
  MT=16,17,37,91 EVAPORATION SPECTRUM.                            
  MT=18    FISSION SPECTRUM ESTIMATED FROM Z**2/A SYSTEMATICS BY  
           SMITH ET AL. /18/ BY ASSUMING E(CF-252) = 2.13 MEV.    
                                                                  
REFERENCES                                                        
 1) NAKAGAWA T. AND IGARASI S.: JAERI-M 9601 (1981).              
 2) NAKAGAWA T.: TO BE PUBLISHED AS JAERI-M REPORT.               
 3) TUTTLE R.J.: INDC(NDS)-107/G+SPECIAL, 29 (1979).              
 4) JAFFEY A.H. AND LERNER J.L.: NUCL. PHYS., A145, 1, (1970).    
 5) ZHURAVLEV K.D. ET AL. : PROC. 2ND NAT. SOVIET CONF. ON NEUT.  
    PHYS., VOL.4, 57 (1974).                                      
 6) HOWERTON R.J.: NUCL. SCI. ENG., 62, 438 (1977).               
 7) ANUFRIEV V.A. ET AL.: SOV. AT. ENERGY, 51, 736 (1982).        
 8) MUGHABGHAB S.F.: "NEUTRON CROSS SECTIONS, VOL.1, PART B",     
    ACADEMIC PRESS (1984).                                        
 9) KIKUCHI Y.: PRIVATE COMMUNICATION.                            
10) SILBERT M.G.: LA-6239 (1976).                                 
11) IGARASI S.: J. NUCL. SCI. TECHNOL., 12, 67 (1975).            
12) IGARASI S. AND NAKAGAWA T.: JAERI-M 8342 (1979).              
13) PHILLIPS T.W. AND HOWE R.E.: NUCL. SCI. ENG. 69, 375 (1979).  
14) ELLIS-AKOVALI Y.A.: NUCL. DATA SHEETS, 44, 407 (1985).        
15) ENSDF, EVALUATED NUCLEAR STRUCTURE DATA FILE, AS OF JAN. 1989.
16) PEARLSTEIN S.: J. NUCL. ENERGY 27, 81 (1973).                 
17) FOMUSHKIN E.F. ET AL.: SOV. AT. ENERGY, 62, 337 (1987).       
18) A.B. SMITH ET AL. : ANL/NDM-50 (1979).