53-I -129

 53-I -129 JNDC       EVAL-MAR90 JNDC FP NUCLEAR DATA W.G.        
                      DIST-NOV90                                  
----JENDL-3.2         MATERIAL 5331                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
HISTORY                                                           
84-10 EVALUATION FOR JENDL-2 WAS MADE BY JNDC FPND W.G./1/        
90-03 MODIFICATION FOR JENDL-3 WAS MADE/2/.                       
                                                                  
MF = 1  GENERAL INFORMATION                                       
  MT=451 COMMENTS AND DICTIONARY                                  
                                                                  
MF = 2  RESONANCE PARAMETERS                                      
  MT=151 RESOLVED AND UNRESOLVED RESONANCE PARAMETERS             
  RESOLVED RESONANCE REGION (MLBW FORMULA) : BELOW 3.391 KEV      
    RESONANCE PARAMETERS OF JENDL-2 WERE MODIFIED AS FOLLOWS :    
    EVALUATION FOR JENDL-2 WAS CARRIED OUT ON THE BASIS OF THE    
    DATA MEASURED BY MACKLIN/3/.  RESONANCE ENERGIES FOR 125      
    LEVELS WERE BASED ON THE MEASUREMENT BY MACKLIN EXCEPT THE 1ST
    LEVEL.  NEUTRON ORBITAL ANGULAR MOMENTUM L WAS ASSUMED TO BE 0
    FOR ALL RESONANCE LEVELS.  RADIATION WIDTH FOR EACH RESONANCE 
    LEVEL WAS NOT GIVEN BY MACKLIN.  THEREFORE, AVERAGE RADIATION 
    WIDTH OF 120 MEV WAS ASSUMED BY TAKING ACCOUNT OF THE MAXIMUM 
    VALUE (58.5 MEV) OF NEUTRON CAPTURE AREAS MEASURED BY MACKLIN.
    NEUTRON WIDTHS WERE DERIVED FROM THE NEUTRON CAPTURE AREAS AND
    THE AVERAGE RADIATION WIDTH.  SINCE THE VALUES OF TOTAL SPIN  
    FOR ALL RESONANCE LEVELS WERE UNKNOWN, THE TARGET SPIN OF 3.5 
    WAS ADOPTED AS THEIR TOTAL SPIN.  A NEGATIVE RESONANCE WAS    
    ADDED AT -10 EV SO AS TO REPRODUCE THE THERMAL CAPTURE CROSS  
    SECTION OF 27 BARNS GIVEN BY MUGHABGHAB ET AL./4/ SCATTERING  
    RADIUS WAS TAKEN FROM THE GRAPH (FIG. 1, PART A) GIVEN IN     
    REF./4/.                                                      
                                                                  
    FOR JENDL-3, THE TOTAL SPIN OF 126 RESONANCE LEVELS WAS       
    TENTATIVELY ESTIMATED WITH A RANDOM NUMBER METHOD.  NEUTRON   
    WIDTHS OF THESE LEVELS WERE MODIFIED ON THE BASIS OF THE      
    ESTIMATED J-VALUES.  NEUTRON AND RADIATION WIDTHS OF THE      
    NEGATIVE RESONANCE LEVEL WERE ALSO MODIFIED SO AS TO REPRODUCE
    THE THERMAL CAPTURE CROSS SECTION ACCORDING TO THE ABOVE      
    MODIFICATION OF THE NEUTRON WIDTHS.                           
                                                                  
  UNRESOLVED RESONANCE REGION : 3.391 KEV - 100 KEV               
    UNRESOLVED RESONANCE PARAMETERS WERE ADOPTED FROM JENDL-2.    
    THE PARAMETERS WERE ADJUSTED TO REPRODUCE THE CAPTURE CROSS   
    SECTION MEASURED BY MACKLIN /3/.  THE EFFECTIVE SCATTERING    
    RADIUS WAS OBTAINED FROM FITTING TO THE CALCULATED TOTAL CROSS
    SECTION AT 100 KEV.                                           
                                                                  
  TYPICAL VALUES OF THE PARAMETERS AT 70 KEV:                     
    S0 = 0.532E-4, S1 = 1.332E-4, S2 = 0.887E-4, SG = 51.8E-4,    
    GG = 0.160 EV, R  = 5.390 FM.                                 
                                                                  
  CALCULATED 2200-M/S CROSS SECTIONS AND RES. INTEGRALS (BARNS)   
                     2200 M/S               RES. INTEG.           
      TOTAL          33.47                     -                  
      ELASTIC         6.471                    -                  
      CAPTURE        27.00                     29.4               
                                                                  
MF = 3  NEUTRON CROSS SECTIONS                                    
  BELOW 100 KEV, RESONANCE PARAMETERS WERE GIVEN.                 
  ABOVE 100 KEV, THE SPHERICAL OPTICAL AND STATISTICAL MODEL      
  CALCULATION WAS PERFORMED WITH CASTHY/5/, BY TAKING ACCOUNT OF  
  COMPETING REACTIONS, OF WHICH CROSS SECTIONS WERE CALCULATED    
  WITH PEGASUS/6/ STANDING ON A PREEQUILIBRIUM AND MULTI-STEP     
  EVAPORATION MODEL.  THE OMP'S FOR NEUTRON GIVEN IN TABLE 1 WERE 
  DETERMINED TO REPRODUCE A SYSTEMATIC TREND OF THE TOTAL CROSS   
  SECTION, CHANGED FROM R0 AND RSO OF IIJIMA AND KAWAI/7/.  THE   
  OMP'S FOR CHARGED PARTICLES ARE AS FOLLOWS:                     
     PROTON   = PEREY/8/                                          
     ALPHA    = HUIZENGA AND IGO/9/                               
     DEUTERON = LOHR AND HAEBERLI/10/                             
     HELIUM-3 AND TRITON = BECCHETTI AND GREENLEES/11/            
  PARAMETERS FOR THE COMPOSITE LEVEL DENSITY FORMULA OF GILBERT   
  AND CAMERON/12/ WERE EVALUATED BY IIJIMA ET AL./13/  MORE       
  EXTENSIVE DETERMINATION AND MODIFICATION WERE MADE IN THE       
  PRESENT WORK.  TABLE 2 SHOWS THE LEVEL DENSITY PARAMETERS USED  
  IN THE PRESENT CALCULATION.  ENERGY DEPENDENCE OF SPIN CUT-OFF  
  PARAMETER IN THE ENERGY RANGE BELOW E-JOINT IS DUE TO GRUPPELAAR
  /14/.                                                           
                                                                  
  MT = 1  TOTAL                                                   
    SPHERICAL OPTICAL MODEL CALCULATION WAS ADOPTED.              
                                                                  
  MT = 2  ELASTIC SCATTERING                                      
    CALCULATED AS (TOTAL - SUM OF PARTIAL CROSS SECTIONS).        
                                                                  
  MT = 4, 51 - 91  INELASTIC SCATTERING                           
    SPHERICAL OPTICAL AND STATISTICAL MODEL CALCULATION WAS       
    ADOPTED.  THE LEVEL SCHEME WAS TAKEN FROM REF./15/            
                                                                  
           NO.      ENERGY(MEV)    SPIN-PARITY                    
           GR.       0.0            7/2 +                         
            1        0.0278         5/2 +                         
            2        0.2784         3/2 +                         
            3        0.4874         5/2 +                         
            4        0.5596         1/2 +                         
            5        0.6960        11/2 +                         
            6        0.7296         9/2 +                         
            7        0.7689         7/2 +                         
            8        0.8299         3/2 +                         
            9        0.8450         7/2 +                         
           10        1.0470         3/2 +                         
           11        1.0504         7/2 +                         
           12        1.1117         5/2 +                         
           13        1.2100         1/2 +                         
           14        1.2608         5/2 +                         
           15        1.2821         3/2 +                         
           16        1.2922         1/2 +                         
           17        1.4016         9/2 +                         
           18        1.4835         1/2 +                         
      LEVELS ABOVE 1.55 MEV WERE ASSUMED TO BE OVERLAPPING.       
                                                                  
  MT = 102  CAPTURE                                               
    SPHERICAL OPTICAL AND STATISTICAL MODEL CALCULATION WITH      
    CASTHY WAS ADOPTED.  DIRECT AND SEMI-DIRECT CAPTURE CROSS     
    SECTIONS WERE ESTIMATED ACCORDING TO THE PROCEDURE OF BENZI   
    AND REFFO/16/ AND NORMALIZED TO 1 MILLI-BARN AT 14 MEV.       
                                                                  
    THE GAMMA-RAY STRENGTH FUNCTION (5.13E-03) WAS ADJUSTED TO    
    REPRODUCE THE CAPTURE CROSS SECTION OF 215 MILLI-BARNS AT 100 
    KEV MEASURED BY MACKLIN./3/                                   
                                                                  
  MT = 16  (N,2N) CROSS SECTION                                   
  MT = 17  (N,3N) CROSS SECTION                                   
  MT = 22  (N,N'A) CROSS SECTION                                  
  MT = 28  (N,N'P) CROSS SECTION                                  
  MT = 32  (N,N'D) CROSS SECTION                                  
  MT = 33  (N,N'T) CROSS SECTION                                  
  MT =103  (N,P) CROSS SECTION                                    
  MT =104  (N,D) CROSS SECTION                                    
  MT =105  (N,T) CROSS SECTION                                    
  MT =107  (N,ALPHA) CROSS SECTION                                
    THESE REACTION CROSS SECTIONS WERE CALCULATED WITH THE        
    PREEQUILIBRIUM AND MULTI-STEP EVAPORATION MODEL CODE PEGASUS. 
                                                                  
    THE KALBACH'S CONSTANT K (= 221.7) WAS ESTIMATED BY THE       
    FORMULA DERIVED FROM KIKUCHI-KAWAI'S FORMALISM/17/ AND LEVEL  
    DENSITY PARAMETERS.                                           
                                                                  
    FINALLY, THE (N,2N), (N,P) AND (N,ALPHA) CROSS SECTIONS WERE  
    NORMALIZED TO THE FOLLOWING VALUES AT 14.5 MEV:               
      (N,2N)      1500.00  MB (SYSTEMATICS OF WEN DEN LU+/18/)    
      (N,P)          3.64  MB (SYSTEMATICS OF FORREST/19/)        
      (N,ALPHA)      1.86  MB (SYSTEMATICS OF FORREST)            
                                                                  
  MT = 251  MU-BAR                                                
    CALCULATED WITH CASTHY.                                       
                                                                  
MF = 4  ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS               
  LEGENDRE POLYNOMIAL COEFFICIENTS FOR ANGULAR DISTRIBUTIONS ARE  
  GIVEN IN THE CENTER-OF-MASS SYSTEM FOR MT=2 AND DISCRETE INELAS-
  TIC LEVELS, AND IN THE LABORATORY SYSTEM FOR MT=91.  THEY WERE  
  CALCULATED WITH CASTHY.  FOR OTHER REACTIONS, ISOTROPIC DISTRI- 
  BUTIONS IN THE LABORATORY SYSTEM WERE ASSUMED.                  
                                                                  
MF = 5  ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS                
  ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS WERE CALCULATED WITH 
  PEGASUS FOR INELASTIC SCATTERING FROM OVERLAPPING LEVELS AND FOR
  OTHER NEUTRON EMITTING REACTIONS.                               
                                                                  
TABLE 1  NEUTRON OPTICAL POTENTIAL PARAMETERS                     
                                                                  
                DEPTH (MEV)       RADIUS(FM)    DIFFUSENESS(FM)   
         ----------------------   ------------  ---------------   
        V  = 45.97-0.199E         R0 = 6.481    A0 = 0.62         
        WS = 6.502                RS = 6.926    AS = 0.35         
        VSO= 7.0                  RSO= 6.49     ASO= 0.62         
  THE FORM OF SURFACE ABSORPTION PART IS DER. WOODS-SAXON TYPE.   
                                                                  
TABLE 2  LEVEL DENSITY PARAMETERS                                 
                                                                  
 NUCLIDE       A(1/MEV)  T(MEV)    C(1/MEV)  EX(MEV)   PAIRING    
 ---------------------------------------------------------------  
 51-SB-125     1.700E+01 5.120E-01 7.883E-01 3.792E+00 1.090E+00  
 51-SB-126     1.700E+01 5.250E-01 7.566E+00 2.897E+00 0.0        
 51-SB-127     1.700E+01 5.120E-01 6.326E-01 3.902E+00 1.200E+00  
 51-SB-128     1.468E+01 5.600E-01 4.264E+00 2.658E+00 0.0        
                                                                  
 52-TE-126     1.706E+01 6.100E-01 5.154E-01 6.554E+00 2.230E+00  
 52-TE-127     2.004E+01 5.380E-01 3.633E+00 5.165E+00 1.140E+00  
 52-TE-128     1.800E+01 6.090E-01 6.586E-01 7.010E+00 2.340E+00  
 52-TE-129     2.015E+01 5.350E-01 3.588E+00 5.141E+00 1.140E+00  
                                                                  
 53-I -127     1.717E+01 6.263E-01 4.458E+00 5.757E+00 1.090E+00  
 53-I -128     1.715E+01 6.200E-01 2.329E+01 4.542E+00 0.0        
 53-I -129     1.720E+01 6.200E-01 3.436E+00 5.762E+00 1.200E+00  
 53-I -130     1.640E+01 6.000E-01 1.297E+01 3.896E+00 0.0        
 ---------------------------------------------------------------  
                                                                  
 SPIN CUTOFF PARAMETERS WERE CALCULATED AS 0.146*SQRT(A)*A**(2/3).
 IN THE CASTHY CALCULATION, SPIN CUTOFF FACTORS AT 0 MEV WERE     
 ASSUMED TO BE 5.277 FOR I -129 AND 5.0 FOR I -130.               
                                                                  
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    PART A", ACADEMIC PRESS (1981).                               
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14) GRUPPELAAR, H.: ECN-13 (1977).                                
15) MATSUMOTO, J., ET AL.: JAERI-M 7734 (1978).                   
16) BENZI, V. AND REFFO, G.: CCDN-NW/10 (1969).                   
17) KIKUCHI, K. AND KAWAI, M.: "NUCLEAR MATTER AND NUCLEAR        
    REACTIONS", NORTH HOLLAND (1968).                             
18) WEN DEN LU AND FINK, R.W.: PHYS. REV., C4, 1173 (1971).       
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