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50-Sn-122 JNDC EVAL-MAR90 JNDC FP NUCLEAR DATA W.G. DIST-JAN09 20090105 ----JEFF-311 MATERIAL 5055 -----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/ 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 29 KEV RESONANCE PARAMETERS WERE EVALUATED AS FOLLOWS: RESONANCE ENERGIES AND NEUTRON WIDTHS WERE BASED ON MAINLY THE DATA MEASURED BY NAKAJIMA ET AL./2/ AND PARTIALLY THOSE GIVEN BY MUGHABGHAB ET AL./3/ NEUTRON ORBITAL ANGULAR MOMENTUM L OF SOME RESONANCES WAS ESTIMATED WITH A METHOD OF BOLLINGER AND THOMAS/4/. AVERAGED RADIATION WIDTH OF 130 MEV WAS ASSUMED FROM THE SYSTEMATICS OF MEASURED VALUES FOR NEIGHBORING NUCLIDES. SCATTERING RADIUS WAS TAKEN AS 5.7 FM /3/. A NEGATIVE RESONANCE WAS ADDED SO AS TO REPRODUCE THE THERMAL CAPTURE CROSS SECTION GIVEN BY MUGHABGHAB ET AL. UNRESOLVED RESONANCE REGION : 29 KEV - 100 KEV THE NEUTRON STRENGTH FUNCTIONS, S0, S1 AND S2 WERE CALCULATED WITH OPTICAL MODEL CODE CASTHY/5/. 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 = 0.740E-4, S1 = 2.600E-4, S2 = 0.700E-4, SG = 0.297E-4, GG = 0.130 EV, R = 5.564 FM. CALCULATED 2200-M/S CROSS SECTIONS AND RES. INTEGRALS (BARNS) 2200 M/S RES. INTEG. TOTAL 3.979 - ELASTIC 3.795 - CAPTURE 0.1837 0.933 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/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 BY CHANGING RSO OF IIJIMA-KAWAI POTENTIAL/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 BASED ON EVALUATED NUCLEAR STRUCTURE DATA FILE (1987 VERSION)/15/ AND NUCLEAR DATA SHEETS/16/. NO. ENERGY(MEV) SPIN-PARITY GR. 0.0 0 + 1 1.1402 2 + 2 2.0900 0 + 3 2.1450 4 + 4 2.1530 1 + 5 2.2490 5 - 6 2.3360 4 + 7 2.4000 7 - 8 2.4150 2 + 9 2.4920 3 - LEVELS ABOVE 2.556 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/17/ AND NORMALIZED TO 1 MILLI-BARN AT 14 MEV. THE GAMMA-RAY STRENGTH FUNCTION (2.75E-5) WAS ADJUSTED TO REPRODUCE THE CAPTURE CROSS SECTION OF 23 MILLI-BARNS AT 30 KEV MEASURED BY MACKLIN ET AL./18/ 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 (= 241.0) WAS ESTIMATED BY THE FORMULA DERIVED FROM KIKUCHI-KAWAI'S FORMALISM/19/ AND LEVEL DENSITY PARAMETERS. MT = 251 MU-BAR CALCULATED WITH CASTHY/5/. 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-118 * 1.766E+01 6.064E-01 3.562E-01 7.089E+00 2.600E+00 48-CD-119 * 1.742E+01 6.040E-01 2.363E+00 5.715E+00 1.360E+00 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 49-IN-119 1.940E+01 5.340E-01 2.195E+00 4.999E+00 1.240E+00 49-IN-120 * 1.757E+01 6.016E-01 2.330E+01 4.366E+00 0.0 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 50-SN-120 1.595E+01 6.540E-01 4.691E-01 7.083E+00 2.430E+00 50-SN-121 1.630E+01 6.100E-01 2.010E+00 5.217E+00 1.190E+00 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 --------------------------------------------------------------- SYST: * = LDP'S WERE DETERMINED FORM 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 8.569 FOR SN-122 AND 4.541 FOR SN-123. REFERENCES 1) KAWAI, M. ET AL.: PROC. INT. CONF. ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, MITO, P. 569 (1988). 2) NAKAJIMA, Y. ET AL.: ANN. NUCL. ENERGY, 17, 95 (1990). 3) MUGHABGHAB, S.F. ET AL.: "NEUTRON CROSS SECTIONS, VOL. I, PART A", ACADEMIC PRESS (1981). 4) BOLLINGER, L.M. AND THOMAS, G.E.: PHYS. REV., 171,1293(1968). 5) IGARASI, S.: J. NUCL. SCI. TECHNOL., 12, 67 (1975). 6) IIJIMA, S. ET AL.: JAERI-M 87-025, P. 337 (1987). 7) IIJIMA, S. AND KAWAI, M.: J. NUCL. SCI. TECHNOL., 20, 77 (1983). 8) PEREY, F.G: PHYS. REV. 131, 745 (1963). 9) HUIZENGA, J.R. AND IGO, G.: NUCL. PHYS. 29, 462 (1962). 10) LOHR, J.M. AND HAEBERLI, W.: NUCL. PHYS. A232, 381 (1974). 11) 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). 12) GILBERT, A. AND CAMERON, A.G.W.: CAN. J. PHYS., 43, 1446 (1965). 13) IIJIMA, S., ET AL.: J. NUCL. SCI. TECHNOL. 21, 10 (1984). 14) GRUPPELAAR, H.: ECN-13 (1977). 15) ENSDF: EVALUATED NUCLEAR STRUCTURE DATA FILE (JUNE 1987). 16) NUCLEAR DATA SHEETS, 49, 315 (1986). 17) BENZI, V. AND REFFO, G.: CCDN-NW/10 (1969). 18) MACKLIN, R.L., ET AL.: NATURE, 194, 1272 (1962). 19) KIKUCHI, K. AND KAWAI, M.: "NUCLEAR MATTER AND NUCLEAR REACTIONS", NORTH HOLLAND (1968).Back |