PHOTOELECTRIC CROSS-SECTIONS - COMPARISON BETWEEN EXPERIMENTAL AND RENORMALIZED AND UNRENORMALIZED THEORETICAL VALUES

X-ray attenuation coefficients, mu(m), determined for four elements an d eight compounds at 6.400 and 8.041 keV were used to obtain the total photon cross-section for elements in the range 13 less than or equal to Z less than or equal to 30 and for Z = 42 and 73. These were compar ed with the 'present best' values produced by Creagh and Hubbell (ITVC values). Except for those elements whose absorption edges are in the range -1 keV < Delta E < +2 keV (Delta E = E(x) - E(upsilon)), all the other elements had mu(m) values in close agreement with the ITVC valu es. The fractional error in the experimental values were found to be l ess than 2%. The derived photoelectric cross-sections were compared wi th Scofield's renormalized and unrenormalized theoretical values. The experimental results were found to be consistently higher than the ren ormalized theoretical values by about 2-3%.