Compton Scattering of X Rays from Bound Electrons
TL;DR: In this article, the impulse approximation (IA) was used to analyze Compton scattering measurements, and its accuracy was compared with the exact calculations for Compton scattering from a hydrogenic system.
Abstract: Exact and approximate methods for determining the momentum distribution of electronic systems from Compton scattering measurements are presented. The method used previously to analyze Compton scattering measurements, the impulse approximation (IA), is derived from first principles, and its accuracy is compared with the exact calculations for Compton scattering from a hydrogenic system. It is shown that the IA gives very accurate results for weakly bound electrons and that exact calculation may only be necessary to substract out the contributions to Compton scattering from deeply bound core electrons. Experimental results for Compton scattering from helium are presented as a test of the above ideas. Analyzing the results of the experiment in the IA gives a momentum distribution for the weakly bound helium electrons which is in excellent agreement with the momentum distribution obtained from Clementi Hartree-Fock wave functions.
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TL;DR: In this article, the Bethe theory has been updated with a number of new developments which need to be included in that body of material, such as the ${z}^{3}$ effect and the stopping power for particles at extreme relativistic energies.
Abstract: Since the appearance of the title paper, a number of new developments have occurred which need to be included in that body of material. We present additional remarks and clarifications which supplement and update numerous aspects of the Bethe theory discussed in the earlier paper. We also bring the bibliography up to date. Plasma stopping power, the ${z}^{3}$ effect, and stopping power for particles at extreme relativistic energies are among the new topics included. We make several comments on Fano's earlier review article, Ann. Rev. Nucl. Sci. 13, 1 (1963).
1,233 citations
01 Jan 1972
TL;DR: In this paper, the Bethe theory has been updated with a number of new developments which need to be included in that body of material, such as the ${z}^{3}$ effect and the stopping power for particles at extreme relativistic energies.
Abstract: Since the appearance of the title paper, a number of new developments have occurred which need to be included in that body of material. We present additional remarks and clarifications which supplement and update numerous aspects of the Bethe theory discussed in the earlier paper. We also bring the bibliography up to date. Plasma stopping power, the ${z}^{3}$ effect, and stopping power for particles at extreme relativistic energies are among the new topics included. We make several comments on Fano's earlier review article, Ann. Rev. Nucl. Sci. 13, 1 (1963).
832 citations
TL;DR: The Hartree-Fock wavefunctions were used in the numerical calculations for atomic numbers 1 ≤ Z ≤ 36 and relativistic Dirac-Hartree Fock wave functions for atomic number 36 ≤ Z ≥ 102.
734 citations
TL;DR: In this article, the authors developed accurate x-ray scattering techniques to measure the physical properties of dense plasmas for applications in high energy density physics, including inertial confinement fusion, material science, or laboratory astrophysics.
Abstract: Accurate x-ray scattering techniques to measure the physical properties of dense plasmas have been developed for applications in high energy density physics. This class of experiments produces short-lived hot dense states of matter with electron densities in the range of solid density and higher where powerful penetrating x-ray sources have become available for probing. Experiments have employed laser-based x-ray sources that provide sufficient photon numbers in narrow bandwidth spectral lines, allowing spectrally resolved x-ray scattering measurements from these plasmas. The backscattering spectrum accesses the noncollective Compton scattering regime which provides accurate diagnostic information on the temperature, density, and ionization state. The forward scattering spectrum has been shown to measure the collective plasmon oscillations. Besides extracting the standard plasma parameters, density and temperature, forward scattering yields new observables such as a direct measure of collisions and quantum effects. Dense matter theory relates scattering spectra with the dielectric function and structure factors that determine the physical properties of matter. Applications to radiation-heated and shock-compressed matter have demonstrated accurate measurements of compression and heating with up to picosecond temporal resolution. The ongoing development of suitable x-ray sources and facilities will enable experiments in a wide range of research areas including inertial confinement fusion,more » radiation hydrodynamics, material science, or laboratory astrophysics.« less
612 citations
TL;DR: In this article, the authors present a review of the history of the field of Compton-scattered electron scattering and present conditions under which the scattering experiment can be interpreted directly in terms of electron momentum density, and compare the experimental results with gamma-rays, X-rays and electron beams.
Abstract: When radiation is Compton-scattered the emerging beam is Doppler broadened because of the motion of the target electrons. An analysis of this broadened lineshape the Crompton profile, provides detailed information about the electron momentum distribution in the scatter. The technique is particularly sensitive to the behaviour of the slower moving outer electrons involved in bonding in condensed matter and can be used to test their quantum-mechanical description. The review begins with a brief survey of the historical development of the subject to within a decade of the present. The behaviour of quantum systems from a momentum viewpoint, is explained and the conditions under which the scattering experiment can be interpreted directly in terms of electron momentum density are discussed. The experimental techniques with gamma -rays, X-rays and electron beams are compared. Finally, recent results on insulators and conductors are surveyed and the extent to which they challenge conventional assumptions of band theory is critically reviewed.
480 citations
Cites methods from "Compton Scattering of X Rays from B..."
...The seriousness of the failure of the approximation was calculated by Platzman and Tzoar (1963, Eisenberger and Platzman (1970) and Mendelsohn and Biggs (1973)....
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