58-Ce-140 JAEA EVAL-FEB10 S.Kunieda, A.Ichihara, K.Shibata+ DIST-DEC21 20100223 ----JENDL-5 MATERIAL 5837 -----INCIDENT NEUTRON DATA ------ENDF-6 FORMAT History 10-02 Re-evaluation was performed for JENDL-4 above the resoloved resonance region. The resonance parameters are the same as those of JENDL-3.3 (compiled by S. Kunieda). 21-11 revised by O.Iwamoto (MF8/MT4,16,17,22,28,32,102-104,107) JENDL/AD-2017 adopted (MF8/MT105,106) added (MF9/MT107) JENDL/AD-2017 adopted (MF10/MT16) JENDL/AD-2017 based MF= 1 General information MT=451 Descriptive data and directory MF= 2 Resonance parameters MT=151 Resolved and unresolved resonance parameters - Resolved resonance region (MLBW formula): below 200 keV For JENDL-2, the resonance parameters were evaluated by Kikuchi /1/. Neutron widths were obtained from data measured by Hacken et al. /2/ and Camarda /3/, and radiation widths from capture areas by Musgrove et al. /4/ For the resonances only whose capture area was measured, the neutron width was deduced by assuming the average radiation width of 0.034+-0.029 eV for s-wave resonances and 0.029+-0.008 eV for p-wave ones. A negative resonance was added so as to reproduce the capture cross section of 0.57+-0.04 barn and the elastic scattering cross section of 2.83+-0.11 barns at 0.0253 eV /5/. For JENDL-3.2, neutron widths of 14 resonances were replaced with experimental data obtained by Ohkubo /6/ in the energy range from 2.5437 keV to 55.113 keV. Parameters of the negative resonance were re-adjusted to the above thermal cross sections /5/. For JENDL-3.3, neutron widths of 2.5- to 55- keV levels were modified on the basis of Ohkubo et al. /7/. Capture widths of all levels were multiplied by a factor of 1.4 so as to be consistent with a new capture cross section measurement /8/. A negative level was modified and 1/v corresction was aplied to the capture cross section. No further update was made for JENDL-4. - No unresolved resonance parameters are given. Thermal cross sections & resonance integrals at 300 K ---------------------------------------------------------- 0.0253 eV res. integ. (*) (barns) (barns) ---------------------------------------------------------- Total 3.46643E+00 Elastic 2.89398E+00 n,gamma 5.70396E-01 3.44622E-01 ---------------------------------------------------------- (*) Integrated from 0.5 eV to 10 MeV. MF= 3 Neutron cross sections MT= 1 Total cross section Sum of partial cross sections. MT= 2 Elastic scattering cross section The OPTMAN /9/ & POD calculations /10/. MT= 3 Non-elastic cross section Sum of partial non-elastic cross sections. MT= 4,51-91 (n,n') cross section The OPTMAN /9/ & POD calculations /10/. MT= 16 (n,2n) cross section MT= 17 (n,3n) cross section MT= 22 (n,na) cross section MT= 28 (n,np) cross section MT= 32 (n,nd) cross section Calculated by the POD code /10/. MT=102 Capture cross section Calculated by the POD code /10/. Gamma-ray strength function was normalized to fit the experimental cross sections measured by Harnood et al /8/. MT=103 (n,p) cross section MT=104 (n,d) cross section MT=105 (n,t) cross section MT=106 (n,He3) cross section MT=107 (n,a) cross section Calculated by the POD code /10/. MT=203 (n,xp) cross section Sum of (n,np) and (n,p) MT=204 (n,xd) cross section Sum of (n,nd) and (n,d) MT=205 (n,xt) cross section MT=206 (n,xHe3) cross section Calculated by the POD code /10/. MT=207 (n,xa) cross section Sum of (n,na) and (n,a) MF= 4 Angular distributions of emitted neutrons MT= 2 Elastic scattering The OPTMAN /9/ & POD calculations /10/. MF= 6 Energy-angle distributions of emitted particles MT= 16 (n,2n) reaction MT= 17 (n,3n) reaction MT= 22 (n,na) reaction MT= 28 (n,np) reaction MT= 32 (n,nd) reaction Neutron spectra calculated by the POD code /10/. MT= 51-90 (n,n') reaction Neutron angular distributions calculated by OPTMAN /9/ & POD /10/. MT= 91 (n,n') reaction Neutron spectra calculated by the POD code /10/. MT= 203 (n,xp) reaction MT= 204 (n,xd) reaction MT= 205 (n,xt) reaction MT= 206 (n,xHe3) reaction MT= 207 (n,xa) reaction Light-ion spectra calculated by the POD code /6/. MF=12 Gamma-ray multiplicities MT= 3 Non-elastic gamma emission Calculated by the POD code /10/. MF=14 Gamma-ray angular distributions MT= 3 Non-elastic gamma emission Assumed to be isotropic. MF=15 Gamma-ray spectra MT= 3 Non-elastic gamma emission Calculated by the POD code /10/. *************************************************************** * Nuclear Model Calculations with POD Code /10/ * *************************************************************** 1. Theoretical models The POD code is based on the spherical optical model, the distorted-wave Born approximaiton (DWBA), one-component exciton preequilibrium model, and the Hauser-Feshbach-Moldauer statis- tical model. With the preequilibrium model, semi-empirical pickup and knockout process can be taken into account for composite-particle emission. The gamma-ray emission from the compound nucleus can be calculated within the framework of the exciton model. The code is capable of reading in particle transmission coefficients calculated by separate spherical or coupled-channel optical model code. In this evaluation, the OPTMAN code /9/ was employed for neutrons, while the ECIS code /11/ was adopted for charged particles. 2. Optical model & parameters Neutrons: Model: Coupled-channel model based on the rigid-rotor model OMP : Based on the Coupled-channel optical potential /12/ The original Parameters were slightly modified as listed below to reproduce experimental total cross sections measured by Camarda et al /13/. ------------------------------------------------------------ - Real-volume term VR0= -3.85E+1 MeV VR1= 2.70E-2 MeV VR2= 1.20E-4 MeV VR3= 3.50E-7 MeV VRLA= 9.49E+1 MeV ALAVR= 4.22E-3 r= 1.21E+0 a= 6.30E-1 - Imaginary-surface term WDBW= 1.30E+1 MeV WDWID= 1.40E+1 MeV ALAWD= 1.40E-2 r= 1.21E+0 a= 6.75E-1 - Imaginary-volume term WCBW= 1.70E+1 MeV WCWID= 1.05E+2 MeV r= 1.21E+0 a= 6.75E-1 - Spin-orbit term VS= 6.34E+0 MeV ALASO= 5.00E-3 WSBW= -3.10E+0 MeV WSWID= 1.60E+2 MeV r= 1.05E+0 a= 5.90E-1 - Isospin coefficients CISO= 2.43E+1 WCISO= 1.80E+1 CCOUL= 9.00E-1 - Deformation parameter Beta2= 1.60E-1 ------------------------------------------------------------ Protons: Model: Spherical OMP : Koning and Delaroche /14/ Deuterons: Model: Spherical OMP : Bojowald et al. /15/ Tritons: Mode: Spherical OMP : Becchetti and Greenlees /16/ He-3: Model: Spherical OMP : Becchetti and Greenlees /16/ Alphas: Model: Spherical OMP : A simplified folding model potential /17/ (The nucleon OMP was taken form Ref./12/.) 3. Level scheme of Ce-140 ------------------------------------ No. Ex(MeV) J PI CC ------------------------------------ 0 0.00000 0 + * 1 1.59623 2 + * 2 1.90331 0 + 3 2.08325 4 + 4 2.10785 6 + 5 2.34788 2 + 6 2.34981 5 + 7 2.41201 3 + 8 2.46408 3 - 9 2.48092 4 + ------------------------------------ Levels above 2.49092 MeV are assumed to be continuous. 4. Level density parameters Energy-dependent parameters of Mengoni-Nakajima /18/ were used ---------------------------------------------------------- Nuclei a* Pair Esh T E0 Ematch Elv_max 1/MeV MeV MeV MeV MeV MeV MeV ---------------------------------------------------------- Ce-141 17.686 1.011 -1.072 0.493 0.659 3.613 1.942 Ce-140 17.074 2.028 -1.942 0.640 0.903 6.384 2.481 Ce-139 17.607 1.018 -1.120 0.492 0.694 3.570 1.985 Ce-138 16.866 2.043 -0.407 0.654 0.240 7.301 2.237 La-140 17.665 0.000 -1.411 0.615 -1.257 4.391 0.602 La-139 16.263 1.018 -2.218 0.812 -1.629 8.151 1.257 La-138 16.770 0.000 -1.494 0.612 -0.947 3.973 0.642 Ba-138 16.830 2.043 -3.130 0.710 0.829 6.866 3.155 Ba-137 18.884 1.025 -2.239 0.463 0.926 3.110 1.908 Ba-136 16.959 2.058 -1.396 0.750 -0.538 8.774 2.223 ---------------------------------------------------------- 5. Gamma-ray strength functions M1, E2: Standard Lorentzian (SLO) E1 : Generalized Lorentzian (GLO) /19/ 6. Preequilibrium process Preequilibrium is on for n, p, d, t, He-3, and alpha. Preequilibrium capture is on. References 1) Kikuchi Y. et al.: JAERI-M 86-030 (1986). 2) Hacken G., et al.: USNDC-11, 79 (1974). 3) Camarda H.S.: Phys. Rev., C18, 1254 (1978). 4) Musgrove A.R. de L., et al.: Aust. J. Phys., 32, 213 (1979). 5) Mughabghab S.F. et al.: "Neutron Cross Sections, Vol. I, Part A", Academic Press (1981). 6) Ohkubo M. et al.: Proc. Int. Conf. on Nuclear Data for Basic and Applied Science, Santa-Fe., Vol.2, p.1623 (1985). 7) Ohkubu M., et al.: JAERI-M 93-012 (1993). 8) Harnood S., et al.: J. Nucl. Sci. Technol., 37, 740 (2000). 9) E.Soukhovitski et al., JAERI-Data/Code 2005-002 (2005). 10) A.Ichihara et al., JAEA-Data/Code 2007-012 (2007). 11) J.Raynal, CEA Saclay report, CEA-N-2772 (1994). 12) S.Kunieda et al., J. Nucl. Sci. Technol. 44, 838 (2007). 13) Camarda et al., Phys. Rev. C 29, 2106 (1984). 14) A.J.Koning, J.P.Delaroche, Nucl. Phys. A713, 231 (2003). 15) Bojowald et al., Phys. Rev. C 38, 1153 (1988). 16) F.D.Becchetti,Jr., G.W.Greenlees, "Polarization Phenomena in Nuclear Reactions," p.682, The University of Wisconsin Press (1971). 17) D.G.Madland, NEANDC-245 (1988), p. 103. 18) A.Mengoni, Y.Nakajima, J. Nucl. Sci. Technol. 31, 151 (1994). 19) M.Brink, Ph.D thesis, Oxford University, 1955.