A semiempirical formula for the photoelectric cross-section for photon energies up to 1 MeV

The observed disagreement between theoretical and currently accepted data for the photoelectric cross-section motivated us to develop a correction factor which would be able to correct the theoretical expressions in order to account for the currently accepted data. The obtained factor enables correction of the expression developed by Heitler in such a way that the errors relative to the currently accepted data are lower than 3% below 50 keV, and lower than 5% between 50 keV and 1 MeV. Finally, allowing for the fact that the angular dependence of the differential cross-section is well represented by Heitler's formula, the obtained factor may also correct this cross-section. (author)