12-Mg- 0 LLNL EVAL-Jul97 D.E.Cullen, et al. UCRL50400,Vol.6,Rev.5 DIST-MAY10 20100228 ----JENDL-4.0 MATERIAL 1200 -----PHOTO-ATOMIC INTERACTION DATA ------ENDF-6 FORMAT ================================================================= The data were taken from EPDL97. ================================================================= The Livermore Evaluated Photon Data Library (EPDL97) in the ENDF/B-VI format ================================================================= Contents ================================================================= MF/MT Description ================================================================= 23/501 Total cross sections 23/502 Coherent scattering cross sections 23/504 Incoherent scattering cross sections 23/515 Pair production cross sections, Electron field 23/516 Pair production cross sections, Total 23/517 Pair production cross sections, Nuclear field 23/522 Total photoionization cross section 23/534 K (1S1/2) Photoionization subshell cross section 23/535 L1 (2S1/2) Photoionization subshell cross section 23/536 L2 (2P1/2) Photoionization subshell cross section 23/537 L3 (2P3/2) Photoionization subshell cross section 23/538 M1 (3S1/2) Photoionization subshell cross section ================================================================= 27/502 Coherent scattering form factors 27/504 Incoherent scattering functions 27/505 Imaginary anomalous scattering factor 27/506 Real anomalous scattering factor ================================================================= Warning ================================================================= MF/MT combinations used to define photoionization subshell cross sections (MF=23, MT=534-572) and coherent anomalous scattering factors (MF=27, MT=505 AND 506) are newly defined MF/MT numbers for ENDF/B-VI that did not exist in earlier versions of ENDF/B. If you are not prepared to use this data you need merely delete it and all of the remaining data will still be consistent and equivalent to the types of data in earlier versions of ENDF/B. However, this will limit the range of problems to which this data can be applied (see: ref. 1 for details). ================================================================= Definition of new types of data ================================================================= 1) The total photoionization cross section is equal to the sum of the photoionization subshell cross sections. For each subshell on the second line of a section the C1 and C2 fields are defined as, EPE = The photoionization edge energy (similar to Q-value) EFL = The fluorescence yield (eV/photoionization) 2) The angular distribution of coherently scattered photons is, S(E,MU) = 3*T/8*(1 + MU**2)*((FF(M)+F1(E))**2+(F2(E))**2) S(E,MU) = Angular distributions (barns per unit cosine) T = The Thomson cross section MU = The cosine of the scattering angle FF(M) = The atomic form factor M = Momentum transfer = SIN(THETA/2)/LAMBDA/4*PI F1(E) = The real anomalous scattering factor F2(E) = The imaginary anomalous scattering factor F1(E) and F2(E) are isotropic. When F1(E) = F2(E) = 0 this reduces to the result obtained using only form factors (the older ENDF/B convention). ================================================================= Differences between EPDL97 and the data base presented here ================================================================= 1) Energy range - EPDL97 - 1 eV to 100 GeV Here - 1 eV TO 100 GeV (previously 100 MeV) 2) Type of Data - EPDL97 - Photon interaction including photoexcitation Here - Photon interaction - ENDF/B-VI has no provision for photoexcitation 3) Secondary E - EPDL97 - Average energy of each secondary (photons, electrons, positrons) HERE - No secondary energy data 4) Interpolation- EPDL97 - Cross sections are Log X vs. Log Y interpolable - the total cross section is not included - Form factors and scattering functions are Log X vs. Log y, except first interval. - Anomalous scattering factors linearly interpolable (they can be negative) Here - Up through ENDF/B-V photon interaction cross sections were Log X vs. Log Y. - For the first two Mods. of ENDF/B-VI in order to consistently define the total cross sections at ALL energies all cross sections were linearized. This was NOT a good idea. - Starting with Mod. 3, cross sections are left in Log X vs. Log. Y form so that they are IDENTICAL to what's in EPDL97. The total is defined ONLY at the energies tabulated in any other cross section. WARNING - As a result the total cross section MUST NOT be interpolated to define the total between tabulated energies. The ONLY consist way to define the total between tabulated energies is to interpolate all of the partials and add them up. ================================================================= References ================================================================= 1) D.E. Cullen, M.H. Chen, J.H. Hubbell, S.T. Perkins, E.F. Plechaty, J.A. Rathkopf and J.H. Scofield, Tables and graphs of photon interaction cross sections from 10 eV to 100 GeV derived from the LLNL Evaluated Photon data library (EPDL), UCRL-50400, Vol. 6, Rev. 4, Part A: Z = 1 to 50 and Part B: Z = 51 to 100, Lawrence Livermore National Laboratory (1989) 2) D.E. Cullen, J.H. Hubbell and L.D. Kissel, EPDL97: the Evaluated Photon Data Library, '97 Version, UCRL-50400, Vol. 6, Rev. 5, Lawrence Livermore National Laboratory (1997) These are the primary references to the contents of this library and they contain a complete list of references to the sources of data used in this library, methods of evaluation, accuracy of the data, etc. ================================================================= History ================================================================= Mod. 1 - October, 1989 - Initial release. Mod. 2 - August, 1990 - Updated photoionization total and subshell cross sections. Mod. 3 - July, 1997 - Complete re-evaluation. =================================================================