
Accession Number : ADA119277
Title : On the Prediction and Application of Low Energy XRay Interactions,
Descriptive Note : Proceedings publication 1 Oct 8130 Sep 82,
Corporate Author : HAWAII UNIV HONOLULU DEPT OF PHYSICS AND ASTRONOMY
Personal Author(s) : Henke,Burton L
PDF Url : ADA119277
Report Date : Jan 1982
Pagination or Media Count : 75
Abstract : For the low energy xray region of 1002000 eV, the complete atomic interaction, coherent scattering and photoelectric absorption can be described by a complex scattering amplitude which may be given through the atomic scattering factor, f1 + if2. For this low photon energy region, it is shown by the relativistic quantum dispersion theory that the atomic scattering factors can be uniquely determined from simple relations involving only the atomic photoionization cross section dependence upon phonton energy. We have compiled state of the art tables for the photoionization cross sections for 94 elements and for the photon energy region of 3010,000 eV. With this compilation, we have established atomic scattering factor tables for the 1002000 eV region. By a summing of the complex, atomic scattering amplitudes, a low energy xray interaction can be determined. Even for atoms in the molecular or solid state the scattering cross sectons remain atomiclike except for photon energies very near the thresholds. Using practical examples, the methods of calculation, with the atomic scattering factors, are reviewed here for the following: xray energy deposition within materials (energy response of xray photocathodes); transmission through a homogeneous medium: refraction; transmission through a random collection of uniform spheres: low angle scattering in an inhomogeneous medium; specular, Fresnel reflection (total and large angle reflection) at smooth boundary; and Bragg reflection from a periodic, layered system(reflection by crystals and multilayers). (Author)
Descriptors : *X rays, *Low energy, *Interactions, *Coherent scattering, X ray absorption analysis, Atoms, Low angles, Molecular structure, Cross sections, Photoionization, Photons, Photocathodes, Bragg angle, Deposition
Subject Categories : Nuclear Physics & Elementary Particle Physics
Distribution Statement : APPROVED FOR PUBLIC RELEASE