RTAB data files are available at:
ftp://www-phys.llnl.gov/pub/rayleigh/RTAB

9. Photoeffect cross sections, 0-50 MeV (data_PE)

Our evaluation of the photoeffect cross section starts with a modified version of the PIXS code due to Scofield (see, for example, Saloman et al., 1988). We directly compute subshell photoeffect cross sections in our potential to obtain total-atom cross sections up to several hundred keV. These values are stored in the RTAB database in files with the filename 'ZZZ_peIM', where 'ZZZ', 'I' and 'M' indicate the atomic number, ioniticity, and model as noted earlier, and '_pe' indicates that the file contains photoeffect cross sections. For example, the file 'data_PE/082_pe0sl' contains our direct evaluation of subshell and total-atom photoeffect cross sections from threshold to several hundred keV.

For higher energies, these values are smoothly joined to the total-atom values in the EPDL (Cullen et al., 1997) which extends the photoeffect cross sections up to 100 GeV. These extended photoeffect cross sections are stored in a separate file. For example, the file 'data_PE/082_pe0slx' contains our extended total-atom photoeffect cross sections from threshold to 100 GeV.

Selected total-atom photoeffect cross sections for Pb are listed in Table 7.

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Information date: Sep. 2, 2000 lk