14-Si- 28

 14-SI- 28 TIT,JAERI  EVAL-MAR88 H.KITAZAWA,Y.HARIMA,T.FUKAHORI   
                      DIST-SEP89 REV2-JAN94                       
----JENDL-3.2         MATERIAL 1425                               
-----INCIDENT NEUTRON DATA                                        
------ENDF-6 FORMAT                                               
HISTORY                                                           
88-03  NEW EVALUATION WAS PERFORMED FOR JENDL-3 BY KITAZAWA,      
       HARIMA (TOKYO INSTITUTE OF TECH.) AND FUKAHORI (JAERI).    
       DETAILS ARE GIVEN IN REF./1/.                              
88-03  COMPILED BY FUKAHORI.                                      
94-01  JENDL-3.2.                                                 
       COMPILED BY T.NAKAGAWA (NDC/JAERI)                         
                                                                  
     *****   MODIFIED PARTS FOR JENDL-3.2   ********************  
      (3,2)                EFFECTS OF MODIFICATION OF INELASTIC   
                           SCATTERING CROSS SECTIONS.             
      (3,4), (3,51-66)     CROSS-SECTION CURVES WERE SMOOTHED.    
      (4,16-28), (4,91)    TAKEN FROM JENDL FUSION FILE           
      (5,16-91)            TAKEN FROM JENDL FUSION FILE           
      (12,102)                                                    
     ***********************************************************  
                                                                  
     -------------------------------------------------------------
      JENDL FUSION FILE /2/  (AS OF JAN. 1994)                    
          EVALUATED AND COMPILED BY S.CHIBA (NDC/JAERI)           
                                                                  
          CROSS SECTIONS, ANGULAR DISTRIBUTIONS AND ENERGY DISTRI-
       BUTIONS WERE TAKEN FROM JENDL-3.1.  MF=6 OF MT=16, 22, 28, 
       AND 91 WERE CREATED BY F15TOB PROGRAM/2/ BY USING KUMABE'S 
       SYSTEMATICS/3/.  THE PRECOMPOUND/COMPOUND RATIO WAS TAKEN  
       FROM THE SINCROS-II CALCULATION/4/.                        
          OPTICAL-MODEL, LEVEL DENSITY AND OTHER PARAMETERS USED  
       IN THE SINCROS-II CALCULATION ARE DESCRIBED IN REF./4/.    
     -------------------------------------------------------------
                                                                  
                                                                  
MF=1  GENERAL INFORMATION                                         
 MT=451   DESCRIPTIVE DATA AND DICTIONARY                         
                                                                  
MF=2  RESONANCE PARAMETERS:                                       
 MT=151                                                           
   RESOLVED RESONANCES  : 1.0E-5 EV - 1.81 MEV                    
   THE RESONANCE PARAMETERS WERE SEARCHED, USING MLBW FORMULA.    
   AN INITIAL GUESS OF THE PARAMETERS WAS TAKEN FROM REF./5/.     
                                                                  
    CALCULATED 2200-M/S CROSS SECTIONS AND RESONANCE INTEGRALS    
                  2200-M/SEC    RES. INTEG.                       
      ELASTIC       2.149 B          -                            
      CAPTURE       0.177 B       0.085 B                         
      TOTAL         2.325 B          -                            
                                                                  
MF=3  NEUTRON CROSS  SECTIONS                                     
 MT=1      TOTAL CROSS SECTION                                    
   BETWEEN 1.81 AND 12.5 MEV, THE CROSS SECTIONS WERE OBTAINED BY 
   AN EYE-GUIDE SO AS TO FOLLOW THE EXPERIMENTAL DATA.  ABOVE 12.5
   MEV, THE CROSS SECTIONS WERE CALCULATED WITH THE STATISTICAL-  
   MODEL CODE CASTHY./1,6/                                        
                                                                  
 MT=2      ELASTIC SCATTERING CROSS SECTIONS                      
   OBTAINED BY SUBTRACTING PARTIAL CROSS SECTIONS FROM THE TOTAL  
   CROSS SECTIONS.                                                
                                                                  
 MT=4,51-66,91  INELASTIC SCATTERING CROSS SECTIONS               
   CALCULATED WITH THE STATISTICAL-MODEL CODE CASTHY /6/ AND THE  
   COUPLED-CHANNEL MODEL CODE ECIS /7/ OR JUPITOR-1 /8/, TAKING   
   ACCOUNT OF COMPETITIVE PROCESSES FOR NEUTRON, PROTON, ALPHA-   
   PARTICLE AND GAMMA-RAY EMISSION./1/ BELOW 11 MEV, THE IMAGINARY
   POTENTIAL STRENGTH OF THE NEUTRON SPHERICAL OPTICAL POTENTIAL  
   WAS MODIFIED FROM THAT IN REF./1/ TO BE W = 1.09 + 0.55*E      
   (MEV).                                                         
                                                                  
   LEVEL SCHEME WAS TAKEN FROM REF./9/.                           
         NO.   ENERGY(MEV)  SPIN-PARITY                           
         G.S.    0.0          0 +                                 
           1.    1.7789       2 +                                 
           2.    4.6178       4 +                                 
           3.    4.9791       0 +                                 
           4.    6.2765       3 +                                 
           5.    6.6914       0 +                                 
           6.    6.8786       3 -                                 
           7.    6.8888       4 +                                 
           8.    7.3807       2 +                                 
           9.    7.4173       2 +                                 
          10.    7.7988       3 +                                 
          11.    7.9334       2 +                                 
          12.    8.2590       2 +                                 
          13.    8.3280       1 +                                 
          14.    8.4133       4 -                                 
          15.    8.5430       6 +                                 
          16.    8.5890       3 +                                 
                                                                  
   CONTINUUM LEVELS WERE ASSUMED ABOVE 8.9 MEV.  LEVEL DENSITY WAS
   CALCULATED, USING THE GILBERT-CAMERON FORMULA.  THE LEVEL      
   DENSITY PARAMETERS WERE OBTAINED FROM A CUMULATIVE PLOT OF     
   OBSERVED LEVELS/1/.                                            
                                                                  
   FOR JENDL-3.2, CROSS SECTIONS AT THRESHOLD ENERGIES OF THE     
   LEVELS WERE INSERTED BY INTERPOLATING THE CALCULATED CROSS     
   SECTIONS.                                                      
                                                                  
 MT=16   (N,2N) CROSS SECTIONS                                    
   CALCULATED BY THE STATISTICAL MODEL, USING THE GNASH           
   CODE/1,10/.  BELOW 11 MEV, THE IMAGINARY POTENTIAL STRENGTH OF 
   THE NEUTRON SPHERICAL OPTICAL POTENTIAL WAS MODIFIED FROM THAT 
   IN REF./1/ TO BE W = 1.09 + 0.55*E (MEV).                      
                                                                  
 MT=22   (N,NA) CROSS SECTIONS                                    
   CALCULATED BY THE STATISTICAL MODEL, USING THE GNASH           
   CODE/1,10/.  OPTICAL POTENTIAL FOR ALPHA-PARTICLES WAS         
   DETERMINED, USING THE DISPERSION THEORY./11/                   
                                                                  
 MT=28   (N,NP) CROSS SECTIONS                                    
   CALCULATED BY THE STATISTICAL MODEL, USING THE GNASH CODE.     
                                                                  
 MT=102  CAPTURE                                                  
   CALCULATED WITH THE STATISTICAL-MODEL CODE CASTHY /6/ AND THE  
   DIRECT-SEMIDIRECT-MODEL CODE HIKARI /12/.  THE STATISTICAL-    
   MODEL CALCULATIONS WERE NORMALIZED TO 0.6 MB AT 2.0 MEV.       
                                                                  
 MT=103  (N,P) CROSS SECTIONS                                     
   CALCULATED BY THE STATISTICAL MODEL, USING THE GNASH CODE.  THE
   IMAGINARY POTENTIAL STRENGTH OF THE PROTON SPHERICAL OPTICAL   
   MODEL WAS MODIFIED FROM THAT IN REF./1/ TO BE W = 11.0 MEV     
   BETWEEN 11 AND 20 MEV AND W = 8.8 + 0.2*E (MEV) BELOW 11 MEV.  
   THE STRENGTH WAS DETERMINED SO AS TO REPRODUCE OBSERVED VALUES 
   /13/.                                                          
                                                                  
 MT=107  (N,A) CROSS SECTIONS                                     
   CALCULATED BY THE STATISTICAL MODEL, USING THE GNASH CODE.     
   OPTICAL POTENTIAL FOR ALPHA-PARTICLES WAS DETERMINED, USING    
   THE DISPERSION THEORY/11/.                                     
                                                                  
 MT=111  (N,2P) CROSS SECTIONS                                    
   CALCULATED BY THE STATISTICAL MODEL, USING THE GNASH CODE.     
                                                                  
 MT=251  MU-BAR                                                   
   CALCULATED WITH STATISTICAL-MODEL CODE CASTHY /1,6/.           
                                                                  
MF=4    ANGULAR DISTRIBUTIONS OF SECONDARY NEUTRONS               
 MT=2                                                             
   CALCULATED WITH THE STATISTICAL-MODEL CODE CASTHY /1,6/.       
 MT=51-66                                                         
   INCOHERENT SUM OF THE STATISTICAL MODEL AND COUPLED-CHANNEL    
   MODEL CALCULATIONS./1/  CALCULATED WITH CASTHY AND ECIS OR     
   JUPITOR-1.                                                     
 MT=16,22,28,91                                                   
   TAKEN FROM JENDL FUSION FILE.                                  
                                                                  
MF=5    ENERGY DISTRIBUTIONS OF SECONDARY NEUTRONS                
 MT=16,22,28,91                                                   
   TAKEN FROM JENDL FUSION FILE.                                  
                                                                  
MF=12   GAMMA-RAY MULTIPLICITIES (BELOW 9.22088 MEV)              
 MT=51-66,102,103,107                                             
   CALCULATED BY USING THE GNASH CODE/1,10/.  MULTIPLICITIES OF   
   MT=102 WERE DETERMINED FROM ENERGY BALANCE.                    
                                                                  
MF=13   GAMMA-RAY PRODUCTION CROSS SECTIONS (ABOVE 9.22088 MEV)   
 MT=3                                                             
   CALCULATED BY THE STATISTICAL MODEL AND COUPLED-CHANNEL MODEL, 
   USING THE GNASH CODE /10/ AND THE ECIS /7/ OR JUPITOR-1 CODE   
   /8/.  BRANCHING RATIOS FOR TRANSITIONS BETWEEN DISCRETE LEVELS 
   WERE TAKEN FROM REF./9/.  GAMMA-RAY TRANSITION STRENGTH IN     
   THE CONTINUUM WAS CALCULATED BY THE BRINK-AXEL GIANT RESONANCE 
   MODEL FOR E1 TRANSITION AND BY THE WEISSKOPF SINGLE-PARTICLE   
   MODEL FOR E2 AND M1 TRANSITION./1/                             
                                                                  
MF=14   GAMMA-RAY ANGULAR DISTRIBUTIONS                           
 MT=3,51-66,102,103,107                                           
   ISOTROPIC DISTRIBUTION WAS ASSUMED.                            
                                                                  
MF=15   GAMMA-RAY SPECTRA                                         
 MT=3,102,103,107                                                 
   CALCULATED WITH THE GNASH CODE./1,10/                          
                                                                  
REFERENCES                                                        
 1) KITAZAWA H. ET AL.: PROC. INT. CONF. NUCLEAR DATA FOR SCIENCE 
    AND TECHNOLOGY, MITO, 1988, P.473, (1988).                    
 2) CHIBA S. ET AL.: JAERI-M 92-027, P.35 (1992).                 
 3) KUMABE I. ET AL.: NUCL. SCI. ENG., 104, 280 (1990).           
 4) YAMAMURO N.: JAERI-M 90-006 (1990).                           
 5) MUGHABGHAB S.F. ET AL.: "NEUTRON CROSS SECTIONS, VOL. 1 PART  
    A", ACADEMIC PRESS (1981).                                    
 6) IGARASI S. AND FUKAHORI T.: JAERI 1321 (1991).                
 7) RAYNAL J.: COMPUTER PROGRAM ECIS79 FOR COUPLED-CHANNEL        
    CALCULATIONS, 1979 (UNPUBLISHED).                             
 8) TAMURA T.: REV. MOD. PHYS., 37, 679 (1965).                   
 9) ENDT P.M. AND VAN DER LEUN C.: NUCL. PHYS., A310, 1 (1978).   
10) YOUNG P.G. AND ARTHUR E.D.: LA-6947 (1977).                   
11) KITAZAWA H. ET AL.: UNPUBLISHED.                              
12) KITAZAWA H.: COMPUTER PROGRAM HIKARI FOR DIRECT-SEMIDIRECT    
    CAPTURE CALCULATIONS, 1980 (UNPUBLISHED).                     
13) IKEDA Y.: JAERI 1312 (1988).