52-Te-126 JNDC EVAL-MAR90 JNDC FP NUCLEAR DATA W.G. DIST-MAY10 20100202 ----JENDL-4.0 MATERIAL 5243 -----INCIDENT NEUTRON DATA ------ENDF-6 FORMAT =========================================================== 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/ 93-11 JENDL-3.2 was made by JNDC FPND W.G. 10-02 Compiled by A.Ichihara. ***** modified parts for JENDL-3.2 ******************** (2,151) Resolved resonace parameters *********************************************************** ***** modified parts for JENDL-4.0 ******************** (2,151) Resolved resonance parameters were revised by K.Shibata. (2,151) Unresolved resonance parameters were updated. *********************************************************** 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 30 keV For JENDL-3.1, resonance parameters 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 35 meV was tentatively given for those levels. Neutron orbital angular momentum L of some resonances was estimated with a method of Bollinger and Thomas/3/. Averaged radiation width was deduced to be 98 meV and applied to the levels whose radiation width was unknown. The scattering radius of 5.6 fm was taken from Mughabghab et al./2/ A negative resonance was added so as to reproduce the thermal capture cross section given by Mughabghab et al. For JENL-3.2, neutron and radiation width were determined from the neutron widths measured by Tellier et al./4/ and the capture area data by Macklin and Winters/5/ in the energy range above 2.7 keV. The average radiation width of 0.070 eV given by Macklin and Winters was applied to the s-wave resonances whose radiation width had not been determined from the experiments. For the p-wave resonances without known radiation width, the value of 0.100 eV was assumed. In JENDL-4, the energy of a negative resoannce was changed to -52 eV from -32 eV so as reproduce the thermal capture cross section measured by Honzatko et al./6/ Unresolved resonance region : 30 keV - 300 keV The neutron strength function S0 was based on the compilation of Mughabghab et al./2/, and S1 and S2 were calculated with optical model code CASTHY/7/. 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 = 0.280e-4, S1 = 1.700e-4, S2 = 1.000e-4, Sg = 1.41e-4, Gg = 0.150 eV, r = 5.891 fm. The unresolved resonance parameters were recalculated using the ASREP code/8/. The parameters should be used only for self-shielding calculation. Thermal cross sections and resonance integrals at 300 K ---------------------------------------------------------- 0.0253 eV res. integ. (*) (barns) (barns) ---------------------------------------------------------- Total 3.887E+00 Elastic 3.447E+00 n,gamma 4.401E-01 7.95E+00 ---------------------------------------------------------- (*) Integrated from 0.5 eV to 10 MeV. mf = 3 Neutron cross sections Below 30 keV, resolved resonance parameters were given. 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/9/ 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 r0 and rso of Iijima-Kawai potential/10/. The OMP's for charged particles are as follows: proton = Perey/11/ alpha = Huizenga and Igo/12/ deuteron = Lohr and Haeberli/13/ helium-3 and triton = Becchetti and Greenlees/14/ Parameters for the composite level density formula of Gilbert and Cameron/15/ were evaluated by Iijima et al./16/ 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 /17/. 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)/18/ and Nuclear Data Sheets/19/. no. energy(MeV) spin-parity gr. 0.0 0 + 1 0.6663 2 + 2 1.3613 4 + 3 1.4202 2 + 4 1.7755 6 + 5 1.8735 0 + 6 2.0133 4 + 7 2.0453 2 + 8 2.1816 1 - 9 2.2176 5 - 10 2.3094 2 + 11 2.3861 3 - 12 2.3960 5 + 13 2.4213 3 - Levels above 2.44 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/20/ and normalized to 1 milli-barn at 14 MeV. The gamma-ray strength function (1.26e-04) was adjusted to reproduce the capture cross section of 68 milli-barns at 40 keV measured by Bergman and Romanov/21/ 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 (= 113.3) was estimated by the formula derived from Kikuchi-Kawai's formalism/22/ and level density parameters. Finally, the (n,p) and (n,alpha) cross sections were normalized to the following values at 14.5 MeV: (n,p) 5.00 mb (recommended by Forrest/23/) (n,alpha) 2.30 mb (recommended by 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 to 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 --------------------------------------------------------------- 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 51-SB-123 1.585E+01 6.213E-01 1.285E+00 5.469E+00 1.430E+00 51-SB-124 1.696E+01 5.600E-01 1.090E+01 3.433E+00 0.0 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 52-TE-124 1.784E+01 6.740E-01 1.452E+00 8.479E+00 2.570E+00 52-TE-125 1.992E+01 5.590E-01 5.035E+00 5.527E+00 1.140E+00 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 --------------------------------------------------------------- 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 7.509 for Te-126 and 6.066 for Te-127. 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., Thomas, G.E.: Phys. Rev., 171,1293(1968). 4) Tellier, H. and Newstedd, C.M.: Proc. 3rd Int. Conf. on Neutron Cross Sections and Technol., Knoxville, March 1971, p.680 (1971). 5) Macklin, R.L. and Winters, R.R.: ORNL-6561 (1988). 6) Honzatko, J. et al.: Nucl. Phys., A756, 249 (2005). 7) Igarasi, S. and Fukahori, T.: JAERI 1321 (1991). 8) Y.Kikuchi et al., JAERI-Data/Code 99-025 (1999) [in Japanese]. 9) Iijima, S. et al.: JAERI-M 87-025, p. 337 (1987). 10) Iijima, S. and Kawai, M.: J. Nucl. Sci. Technol., 20, 77 (1983). 11) Perey, F.G: Phys. Rev. 131, 745 (1963). 12) Huizenga, J.R. and Igo, G.: Nucl. Phys. 29, 462 (1962). 13) Lohr, J.M. and Haeberli, W.: Nucl. Phys. A232, 381 (1974). 14) 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). 15) Gilbert, A. and Cameron, A.G.W.: Can. J. Phys., 43, 1446 (1965). 16) Iijima, S., et al.: J. Nucl. Sci. Technol. 21, 10 (1984). 17) Gruppelaar, H.: ECN-13 (1977). 18) ENSDF: Evaluated Nuclear Structure Data File (June 1987). 19) Nuclear Data Sheets, 36, 227 (1982). 20) Benzi, V. and Reffo, G.: CCDN-NW/10 (1969). 21) Bergman, A.A. and Romanov, S.A.: Yadernaya Fizika, 20, 252 (1974). 22) Kikuchi, K. and Kawai, M.: "Nuclear Matter and Nuclear Reactions", North Holland (1968). 23) Forrest, R.A.: AERE-R 12419 (1986).