Whole-atom Compton scattering of unpolarized photons in the energy region 17.44 <= E <= 39.91 keV

Scattering cross sections differential with respect to both the scattering angle and the energy of the scattered photons are derived in the impulse ap proximation for Al, Cu, Sn and Pb in the energy region 17.44 less than or e qual to E less than or equal to 39.91 keV at an angle of 90 degrees. Double differential scattering cross sections are evaluated using nonrelativistic and relativistic expressions based on impulse approximation. The differenc e between the two expressions is less than 1%, in the important interval P- z less than or equal to 3 (a.u), With monoenergetic radiation the influence of scattering geometry on the energy broadening is evaluated with respect to the accepted scattering angles and the incident photon energy. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.