37-Rb- 87 JAEA EVAL-AUG09 K.Shibata, A.Ichihara, S.Kunieda DIST-DEC21 20091118 ----JENDL-5 MATERIAL 3731 -----INCIDENT NEUTRON DATA ------ENDF-6 FORMAT History 09-08 Evaluated by K. Shibata, A. Ichihara and S. Kunieda. 09-10 Compiled by K. Shibata. 21-11 revised by O.Iwamoto (MF8/MT4,16,17,22,28,32,102-107) added 21-11 above 20 MeV, JENDL/ImPACT-2018 merged by O.Iwamoto 21-11 (MF6/MT5) recoil spectrum added by O.Iwamoto 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 12.46 keV Resonance parameters of JENDL-2 were modified as follows : Evaluation of JENDL-2 was performed on the basis of the data measured by Ohkubo et al./1/ Among 30 levels measured in the energy region up to 49 keV, 28 levels were assumed to be s-wave, and remaining 2 levels at 267.1 and 376.9 eV to be p-wave. Neutron widths were determined from the 2g*(neutron width) measured by Ohkubo et al. However, the value of total spin J for each resonance level was unknown except only 6 levels assigned by Ohkubo et al. The target spin of 1.5 was adopted for these unknown levels instead of J. Radiation width was obtained to be 166+-8 meV for only one resonance level at 376.9 eV from the measurement by Ohkubo et al. Average radiation width was also estimated to be 166+-30 meV by Ohkubo et al., and was adopted for the other levels. For JENDL-3, the total spin J of 24 resonance levels was tentatively estimated with a random number method. Neutron widths of these levels were modified on the basis of the estimated J-values. Radiation width of the 2nd level at 376.9 eV and average radiation width were also modified to 115.33 and 115.0 meV, respectively, so as to reproduce the thermal capture cross section of 120+-30 mb given by Mughabghab et al./2/ Scattering radius was taken from the graph (Fig. 1, part A) given by Mughabghab et al. No modification was performed for JENDL-4.0. Unresolved resonance region: 12.46 keV - 1 MeV The parameters were obtained by fitting to the total and capture cross sections calculated from POD /3/. The unresolved 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 4.5049E+00 Elastic 4.3849E+00 n,gamma 1.2004E-01 2.7200E+00 ---------------------------------------------------------- (*) Integrated from 0.5 eV to 10 MeV. MF= 3 Neutron cross sections MT= 1 Total cross section Calculated with POD code /3/. MT= 2 Elastic scattering cross section Obtained by subtracting non-elastic cross sections from total cross sections. MT= 3 Non-elastic cross section Sum of partial non-elastic cross sections. MT= 4,51-91 (n,n') cross section Calculated with POD code /3/. MT= 16 (n,2n) cross section Calculated with POD code /3/. MT= 17 (n,3n) cross section Calculated with POD code /3/. MT= 22 (n,na) cross section Calculated with POD code /3/. MT= 28 (n,np) cross section Calculated with POD code /3/. MT= 32 (n,nd) cross section Calculated with POD code /3/. MT=102 Capture cross section Calculated with POD code /3/. MT=103 (n,p) cross section Calculated with POD code /3/. MT=104 (n,d) cross section Calculated with POD code /3/. MT=105 (n,t) cross section Calculated with POD code /3/. MT=106 (n,He3) cross section Calculated with POD code /3/. MT=107 (n,a) cross section Calculated with POD code /3/. MT=203 (n,xp) cross section Calculated with POD code /3/. MT=204 (n,xd) cross section Calculated with POD code /3/. MT=205 (n,xt) cross section Calculated with POD code /3/. MT=206 (n,xHe3) cross section Calculated with POD code /3/. MT=207 (n,xa) cross section Calculated with POD code /3/. MF= 4 Angular distributions of emitted neutrons MT= 2 Elastic scattering Calculated with POD code /3/. MF= 6 Energy-angle distributions of emitted particles MT= 16 (n,2n) reaction Neutron spectra calculated with POD/3/. MT= 17 (n,3n) reaction Neutron spectra calculated with POD/3/. MT= 22 (n,na) reaction Neutron spectra calculated with POD/3/. MT= 28 (n,np) reaction Neutron spectra calculated with POD/3/. MT= 32 (n,nd) reaction Neutron spectra calculated with POD/3/. MT= 51 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 52 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 53 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 54 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 55 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 56 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 57 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 58 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 59 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 60 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 61 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 62 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 63 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 64 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 65 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 66 (n,n') reaction Neutron angular distributions calculated with POD/3/. MT= 91 (n,n') reaction Neutron spectra calculated with POD/3/. MT= 203 (n,xp) reaction Proton spectra calculated with POD/3/. MT= 204 (n,xd) reaction Deuteron spectra calculated with POD/3/. MT= 205 (n,xt) reaction Triton spectra calculated with POD/3/. MT= 206 (n,xHe3) reaction He3 spectra calculated with POD/3/. MT= 207 (n,xa) reaction Alpha spectra calculated with POD/3/. MF=12 Gamma-ray multiplicities MT= 3 Non-elastic gamma emission Calculated with POD code /3/. 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 with POD code /3/. *************************************************************** * Nuclear Model Calculations with POD Code /3/ * *************************************************************** 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 preequilibrim 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. 2. Optical model parameters Neutrons: Coupled-channel optical model parameters /4/ Protons: Koning and Delaroche /5/ Deuterons: Lohr and Haeberli /6/ Tritons: Becchetti and Greenlees /7/ He-3: Becchetti and Greenlees /7/ Alphas: Lemos /8/ potentials modified by Arthur and Young /9/ 3. Level scheme of Rb- 87 ------------------------- No. Ex(MeV) J PI ------------------------- 0 0.00000 3/2 - 1 0.40259 5/2 - 2 0.84544 1/2 - 3 1.34938 7/2 + 4 1.38982 3/2 - 5 1.46300 1/2 - 6 1.57801 3/2 - 7 1.57810 9/2 + 8 1.74058 5/2 - 9 1.89300 1/2 - 10 1.95000 3/2 + 11 2.01300 5/2 - 12 2.28400 3/2 - 13 2.37841 5/2 + 14 2.37900 3/2 + 15 2.39700 1/2 - 16 2.41446 3/2 - ------------------------- Levels above 2.42446 MeV are assumed to be continuous. 4. Level density parameters Energy-dependent parameters of Mengoni-Nakajima /10/ were used ---------------------------------------------------------- Nuclei a* Pair Esh T E0 Ematch Elv_max 1/MeV MeV MeV MeV MeV MeV MeV ---------------------------------------------------------- Rb- 88 10.406 0.000 -0.431 0.771 -0.492 3.809 1.916 Rb- 87 10.932 1.287 -0.777 0.871 -0.070 6.722 2.414 Rb- 86 9.932 0.000 0.007 0.898 -1.348 5.547 1.738 Rb- 85 10.720 1.302 1.529 0.855 -0.855 7.650 2.088 Kr- 87 12.111 1.287 -0.112 0.649 0.793 4.518 3.172 Kr- 86 11.310 2.588 -0.507 0.715 2.085 6.130 3.575 Kr- 85 11.890 1.302 0.718 0.695 0.285 5.433 2.637 Br- 85 10.720 1.302 -0.138 0.819 0.183 6.155 1.944 Br- 84 11.060 0.000 0.608 0.898 -2.409 6.862 0.408 Br- 83 10.507 1.317 1.382 0.813 -0.276 6.734 2.134 ---------------------------------------------------------- 5. Gamma-ray strength functions M1, E2: Standard Lorentzian (SLO) E1 : Generalized Lorentzian (GLO) /11/ 6. Preequilibrium process Preequilibrium is on for n, p, d, t, He-3, and alpha. Preequilibrium capture is on. References 1) M.Ohkubo et al, J. Nucl. Sci. Tech. 21, 254 (1984). 2) S.F.Mughabghab et al., "Neutron Cross Sections, Vol. I, Part A", Academic Press (1981). 3) A.Ichihara et al., JAEA-Data/Code 2007-012 (2007). 4) S.Kunieda et al., J. Nucl. Sci. Technol. 44, 838 (2007). 5) A.J.Koning, J.P.Delaroche, Nucl. Phys. A713, 231 (2003). 6) J.M.Lohr, W.Haeberli, Nucl. Phys. A232, 381 (1974). 7) F.D.Becchetti,Jr., G.W.Greenlees, "Polarization Phenomena in Nuclear Reactions," p.682, The University of Wisconsin Press (1971). 8) O.F.Lemos, Orsay Report, Series A, No.136 (1972). 9) E.D.Arthur, P.G.Young, LA-8626-MS (1980). 10) A.Mengoni, Y.Nakajima, J. Nucl. Sci. Technol. 31, 151 (1994). 11) J.Kopecky, M.Uhl, Nucl. Sci. Eng. 41, 1941 (1990).