73-Ta-181 NAIG EVAL-MAR87 N.YAMAMURO DIST-MAY10 20100120 ----JENDL-4.0 MATERIAL 7328 -----INCIDENT NEUTRON DATA ------ENDF-6 FORMAT HISTORY 76-03 The evaluation for JENDL-1 /1/ was made by H.Yamakoshi (ship research institute) and JENDL-1 compilation group. 83-03 JENDL-1 data were adopted for JENDL-2 and extended to 20 mev. mf=5 was revised, and unresolved resonance parameters were added by Y.Kikuchi (jaeri) /2/. 83-11 Comment data were added. 87-03 The evaluation for JENDL-3 was made by N.Yamamuro (naig). Resonance parameters were added by new experimental data. Neutron cross sections, except total and elastic scattering cross sections, and energy distributions of secondary neutrons and photons were calculated with gnash /3/ and casthy /4/ codes. 94-02 JENDL-3.2. Compiled by T.Nakagawa (ndc/jaeri) ***** Modified parts for JENDL-3.2 ******************** (12,102) Data were determined from energy balance. *********************************************************** 02-02 JENDL-3.3 Compiled by K.Shibata (jaeri) ***** Modified parts for JENDL-3.3 ******************** (1,451) Updated (3,1),(3,2) Re-calculated (3,107) Revised below 500 keV (3,251) Deleted (4,2) Transformation matrix deleted. (5,16-91) Distributions at threshold were changed. ********************************************************** 10-01 JENDL-4.0 Compiled by K.Shibata(jaea) **** Modified parts for JENDL-4.0 ********************* (1,451) Updated (2,151) Unresolved resonance parameters revised (3,1) Re-calculated (3,2),(3,102) Data beween 2.4 keV and 100 keV given ********************************************************** mf=1 General information mt=451 Descriptive data and dictionary mf=2 Resonance parameters mt=151 Resolved and unresolved resonance parameters Resolved parameters for MLBW formula The energy region from 1.0e-5eV to 2.4 keV. Parameters were taken from refs./5,6,7/ for positive resonances, and from ENDF/B-IV for a negative resonance. The radiative width of 0.059ev was assumed for the resonance whose radiative width was unknown. Unresolved parameters In the energy range from 2.4 to 100keV, parameters were determined to reproduce the measured capture cross sections /6,8/. The parameters are as follows, R= 7.8 fm , Dobs= 4.2 eV , radiative width= 0.065 eV, So= 1.7e-04 S1= 2.0e-05 S2= 2.3e-04 nl= 3 ************************************************************ For JENDL-4.0, the unresolved resonance parameters were revised. The parameters should be used only for self- shielding calculations. ************************************************************ calculated 2200-m/sec cross sections and resonance integrals 2200-m/sec res. integ elastic 5.65 b - capture 20.67 b 660.43 b total 26.32 b - mf=3 Neutron cross sections mt=1 Total Evaluated from experimental data. ************************************************************** In JENDL-4.0, the data beween 2.4 and 100 keV were taken from the pointwise file of JENDL-3.3. ************************************************************** mt=2 Elastic scattering (total cross section) - (reaction cross section) mt=4,51-64,91 Inelastic scattering Below 3 MeV,calculated with optical and statistical model code casthy/4/, and above 3 MeV calculated with statistical and preequilibrium model code gnash/3/. Wilmore-Hodgson's optical-model potential parameters/9/ were used, which reproduced the experimental nonelastic cross sections up to 15 MeV. V=47.01-0.267E-0.00118E**2(MeV) Ws=9.52-0.053E (MeV) ro=1.268, as=0.66 (fm) rs=1.241, as=0.48 (fm) The level scheme was adopted from ref./10/. no. energy (MeV) spin-parity g.s. 0.0 7/2+ 1 0.0062 9/2- 2 0.136 9/2+ 3 0.159 11/2- 4 0.301 11/2+ 5 0.338 13/2- 6 0.482 5/2+ 7 0.495 13/2+ 8 0.543 15/2- 9 0.615 1/2+ 10 0.619 3/2+ 11 0.717 15/2+ 12 0.773 17/2- 13 0.965 17/2+ 14 1.028 19/2- Levels above 1.03MeV were assumed to overlapping. Level density parameters used were as follows, 1/MeV pair-E T(MeV) E (MeV) spin-cutoff Ta-178 22.5 0.0 0.54 4.2 13.0 Ta-179 22.0 0.4 0.53 4.2 18.0 Ta-180 22.5 0.0 0.54 4.2 13.0 Ta-181 22.0 0.73 0.52 4.3 29.0 Ta-182 21.8 0.0 0.56 4.3 13.0 mt=16 (n,2n) cross section Calculated with gnash/3/. mt=17 (n,3n) cross section Calculated with gnash/3/. mt=28 (n,n p) cross section Calculated with gnash /3/. mt=102 Radiative capture cross section Calculated with casthy/4/. ************************************************************** In JENDL-4.0, the data beween 2.4 and 100 keV were taken from the pointwise file of JENDL-3.3. ************************************************************** mt=103 (n.p) cross section Calculated with gnash/3/. mf=4 Angular distributions of secondary neutrons mt=2 Calculated with casthy/4/. mt=16,17,28 Isotropic in the laboratory system was assumed. mt=51-64,91 Calculated with casthy/4/. mf=5 Energy distributions of secondary neutrons mt=16,17,28,91 Calculated with gnash/3/. mf=12 Photon production multiplicities (option1) mt=51-64.91,16,17,28,103 Calculated with gnash/3/. mt=102 Rrom energy balance. mf=14 Photon angular distributions Isotropic in the center-of-mass system was assumed. mf=15 Continuous photon energy spectra mt=91,16,17,28,102,103 Calculated with gnash/3/. References 1) Igarasi,S. et al.: JAERI 1261 (1979) 2) (Ed.) Nakagawa,T.: JAERI-M 84-103 (1984) 3) Young,P.G. and Arthur,E.D.: "GNASH, A Preequilibrium Statistical Nuclear-Model Code for Calculation of Cross Sections and Emission Spectra", LA-6974 (1977). 4) Igarasi,S. and Fukahori,T.: JAERI 1321 (1991). 5) Mughabghab,S.F, and Garder,D.I.: BNL325, 3rd ed. (1973). 6) Macklin,R,L,: Nucl,Sci,Eng., 86,362 (1984). 7) Tsubone,I., Nakajima,Y. and Kanda,Y.: Private communication 8) Yamamuro,N., Saito,K., Emoto,T., Wada,t., Fujita,Y. and Kobayashi,K.: J.Nucl.Sci.Technol., 17, 582 (1980). 9) Wilmore,D. and Hodgson,P.E.: Nucl, Phys., 55, 673 (1964). 10) Firestone,R.B.: Nucl, Data Sheets 43, 289 (1984).