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50-Sn-124 JNDC EVAL-MAR90 JNDC FP NUCLEAR DATA W.G. DIST-JAN09 20090105 ----JEFF-311 MATERIAL 5061 -----INCIDENT NEUTRON DATA ------ENDF-6 FORMAT *************************** JEFF-3.1.1 ************************* ** ** ** Original data taken from: JEFF-3.1 ** ** ** ****************************************************************** ***************************** JEFF-3.1 ************************* ** ** ** Original data taken from: JENDL-3.3 ** ** ** ****************************************************************** =========================================================== JENDL-3.2 data were automatically transformed to JENDL-3.3. Interpolation of spectra: 22 (unit base interpolation) (3,251) deleted, T-matrix of (4,2) deleted, and others. =========================================================== HISTORY 90-03 NEW EVALUATION FOR JENDL-3 WAS COMPLETED BY JNDC FPND W.G./1/ 93-03 JENDL-3.2 WAS MADE BY JNDC FPND W.G. ***** MODIFIED PARTS FOR JENDL-3.2 ******************** (2,151) UNRESOLVED RESONANCE PARAMETERS RE-ADJUSTED SO AS TO REPRODUCE THE RE-NORMALIZED CAPTURE CROSS SECTION. (3,102) RE-NORMALIZATION. (3,2), (3,4), (3,51-91) AND ANGULAR DISTRIBUTIONS SMALL EFFECTS OF THE RE-NORMALIZATION OF CAPTURE CROSS SECTION. *********************************************************** 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 10.7 KEV RESONANCE PARAMETERS AND SCATTERING RADIUS WERE BASED ON MUGHABGHAB ET AL./2/ THE LEVELS WHOSE NEUTRON WIDTH WAS UNKNOWN WERE ASSUMED TO BE P-WAVE RESONANCES, AND A REDUCED NEUTRON WIDTH OF 830 MEV WAS TENTATIVELY GIVEN FOR THESE LEVELS. NEUTRON ORBITAL ANGULAR MOMENTUM L OF SOME RESONANCES WAS ESTIMATED WITH A METHOD OF BOLLINGER AND THOMAS/3/. AVERAGED RADIATION WIDTH OF 140 MEV WAS DERIVED FROM THE SYSTEMATICS OF MEASURED VALUES FOR NEIGHBORING NUCLIDES. A NEGATIVE RESONANCE WAS ADDED SO AS TO REPRODUCE THE THERMAL CAPTURE AND ELASTIC SCATTERING CROSS SECTIONS GIVEN BY MUGHABGHAB ET AL. UNRESOLVED RESONANCE REGION : 10.7 KEV - 100 KEV THE NEUTRON STRENGTH FUNCTION S0 WAS BASED ON THE COMPILATION OF MUGHABGHAB ET AL., AND S1 AND S2 WERE CALCULATED WITH OPTICAL MODEL CODE CASTHY/4/. THE OBSERVED LEVEL SPACING WAS DETERMINED TO REPRODUCE THE CAPTURE CROSS SECTION CALCULATED WITH CASTHY. THE EFFECTIVE SCATTERING RADIUS WAS OBTAINED FROM FITTING TO THE CALCULATED TOTAL CROSS SECTION AT 100 KEV. THE RADIATION WIDTH GG WAS BASED ON THE SYSTEMATICS OF MEASURED VALUES FOR NEIGHBORING NUCLIDES. TYPICAL VALUES OF THE PARAMETERS AT 70 KEV: S0 = 0.150E-4, S1 = 2.600E-4, S2 = 0.680E-4, SG = 0.144E-4, GG = 0.140 EV, R = 5.979 FM. CALCULATED 2200-M/S CROSS SECTIONS AND RES. INTEGRALS (BARNS) 2200 M/S RES. INTEG. TOTAL 4.535 - ELASTIC 4.400 - CAPTURE 0.1355 7.86 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, BY TAKING ACCOUNT OF COMPETING REACTIONS, OF WHICH CROSS SECTIONS WERE CALCULATED WITH PEGASUS/5/ STANDING ON A PREEQUILIBRIUM AND MULTI-STEP EVAPORATION MODEL. THE OMP'S FOR NEUTRON GIVEN IN TABLE 1 WERE DETERMINED SO AS TO REPRODUCE A SYSTEMATIC TREND OF THE TOTAL CROSS SECTION BY CHANGING RSO OF IIJIMA-KAWAI POTENTIAL/6/. THE OMP'S FOR CHARGED PARTICLES ARE AS FOLLOWS: PROTON = PEREY/7/ ALPHA = HUIZENGA AND IGO/8/ DEUTERON = LOHR AND HAEBERLI/9/ HELIUM-3 AND TRITON = BECCHETTI AND GREENLEES/10/ PARAMETERS FOR THE COMPOSITE LEVEL DENSITY FORMULA OF GILBERT AND CAMERON/11/ WERE EVALUATED BY IIJIMA ET AL./12/ 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 /13/. 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 BASED ON EVALUATED NUCLEAR STRUCTURE DATA FILE (1987 VERSION)/14/ AND NUCLEAR DATA SHEETS/15/. NO. ENERGY(MEV) SPIN-PARITY GR. 0.0 0 + 1 1.1316 2 + 2 2.1016 4 + 3 2.1293 0 + 4 2.1294 2 + 5 2.1920 2 + 6 2.2045 5 - 7 2.2215 2 + 8 2.3249 7 - 9 2.3664 2 + 10 2.4264 2 + 11 2.4469 8 + 12 2.5680 6 - 13 2.6024 2 + 14 2.6142 3 - 15 2.6866 0 + 16 2.6887 1 - 17 2.7029 4 + 18 2.8363 2 + 19 2.8751 2 + 20 2.8783 2 + LEVELS ABOVE 2.9 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 (0.1286-4) WAS ADJUSTED TO REPRODUCE THE CAPTURE CROSS SECTION OF 8.3 MILLI-BARNS AT 90 KEV MEASURED BY TIMOKHOV ET AL./17/ 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 =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 (= 215.9) WAS ESTIMATED BY THE FORMULA DERIVED FROM KIKUCHI-KAWAI'S FORMALISM/18/ AND LEVEL DENSITY PARAMETERS. FINALLY, THE (N,P) CROSS SECTION WAS NORMALIZED TO THE FOLLOWING VALUE AT 14.5 MEV: (N,P) 1.56 MB (SYSTEMATICS OF FORREST/19/) 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 TO OVERLAPPING LEVELS AND FOR OTHER NEUTRON EMITTING REACTIONS. TABLE 1 NEUTRON OPTICAL POTENTIAL PARAMETERS DEPTH (MEV) RADIUS(FM) DIFFUSENESS(FM) ---------------------- ------------ --------------- V = 47.64-0.473E R0 = 6.256 A0 = 0.62 WS = 9.744 RS = 6.469 AS = 0.35 VSO= 7.0 RSO= 6.241 ASO= 0.62 THE FORM OF SURFACE ABSORPTION PART IS DER. WOODS-SAXON TYPE. TABLE 2 LEVEL DENSITY PARAMETERS NUCLIDE SYST A(1/MEV) T(MEV) C(1/MEV) EX(MEV) PAIRING --------------------------------------------------------------- 48-CD-120 * 1.718E+01 6.016E-01 1.880E-01 7.009E+00 2.790E+00 48-CD-121 * 1.693E+01 5.992E-01 1.734E+00 5.442E+00 1.360E+00 48-CD-122 * 1.667E+01 5.968E-01 2.388E-01 6.394E+00 2.450E+00 48-CD-123 * 1.641E+01 5.943E-01 1.268E+00 5.165E+00 1.360E+00 49-IN-121 1.601E+01 6.060E-01 1.119E+00 5.277E+00 1.430E+00 49-IN-122 * 1.707E+01 5.968E-01 1.737E+01 4.092E+00 0.0 49-IN-123 1.470E+01 6.100E-01 1.134E+00 4.483E+00 1.090E+00 49-IN-124 1.655E+01 5.240E-01 6.345E+00 2.747E+00 0.0 50-SN-122 1.434E+01 7.060E-01 3.423E-01 7.416E+00 2.620E+00 50-SN-123 1.509E+01 6.870E-01 3.062E+00 6.032E+00 1.190E+00 50-SN-124 1.601E+01 6.160E-01 3.224E-01 6.294E+00 2.280E+00 50-SN-125 1.591E+01 6.210E-01 1.927E+00 5.249E+00 1.190E+00 --------------------------------------------------------------- SYST: * = LDP'S WERE DETERMINED FROM SYSTEMATICS. 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 7.975 FOR SN-124 AND 5.0 FOR SN-125. REFERENCES 1) KAWAI, M. ET AL.: J. NUCL. SCI. TECHNOL., 29, 195 (1992). 2) MUGHABGHAB, S.F. ET AL.: "NEUTRON CROSS SECTIONS, VOL. I, PART A", ACADEMIC PRESS (1981). 3) BOLLINGER, L.M. AND THOMAS, G.E.: PHYS. REV., 171,1293(1968). 4) IGARASI, S. AND FUKAHORI, T.: JAERI 1321 (1991). 5) IIJIMA, S. ET AL.: JAERI-M 87-025, P. 337 (1987). 6) IIJIMA, S. AND KAWAI, M.: J. NUCL. SCI. TECHNOL., 20, 77 (1983). 7) PEREY, F.G: PHYS. REV. 131, 745 (1963). 8) HUIZENGA, J.R. AND IGO, G.: NUCL. PHYS. 29, 462 (1962). 9) LOHR, J.M. AND HAEBERLI, W.: NUCL. PHYS. A232, 381 (1974). 10) BECCHETTI, F.D., JR. AND GREENLEES, G.W.: POLARIZATION PHENOMENA IN NUCLEAR REACTIONS ((EDS) H.H. BARSHALL AND W. HAEBERLI), P. 682, THE UNIVERSITY OF WISCONSIN PRESS. (1971). 11) GILBERT, A. AND CAMERON, A.G.W.: CAN. J. PHYS., 43, 1446 (1965). 12) IIJIMA, S., ET AL.: J. NUCL. SCI. TECHNOL. 21, 10 (1984). 13) GRUPPELAAR, H.: ECN-13 (1977). 14) ENSDF: EVALUATED NUCLEAR STRUCTURE DATA FILE (JUNE 1987). 15) NUCLEAR DATA SHEETS, 41, 413 (1984). 16) BENZI, V. AND REFFO, G.: CCDN-NW/10 (1969). 17) TIMOKHOV,V.M., ET AL.:??? 18) KIKUCHI, K. AND KAWAI, M.: "NUCLEAR MATTER AND NUCLEAR REACTIONS", NORTH HOLLAND (1968). 19) FORREST, R.A.: AERE-R 12419 (1986).Back |