[en] Measurements have been made of the recoiling electron in 320 keV gamma ray inelastic scattering collisions in thin aluminium targets. The angular correlation of these electrons detected in coincidence with the scattered photon is in agreement with the kinematic requirements of the Compton effect and is correctly predicted by Monte Carlo simulations based on the impulse approximation. Further simulations of ideal-geometry experiments indicate that information about the initial electron momenta is available from an examination of those electron-photon events originating in a surface layer of one electronic mean free path depth and that elastic scattering of the recoil electrons from greater depths produces a nearly flat background to this signal. The results clearly demonstrate the feasibility of the (γ,eγ) experiment for studying electron momentum densities with synchrotron radiation. (orig.) With 23 refs., 17 figs

[en] The recycling of laser beams in the focal region of non-resonant multipass optical cavities has been investigated as a means of providing a high intensity of photons for weak interaction experiments. Ray-tracing simulations and measurements with an Ar-ion laser have been carried out to examine the intensity profiles of the laser field in different 2-mirror geometries. In particular, the use of such cavities in the generation of X-rays by inverse Compton scattering is considered. X-ray yields are calculated for electron beams of 0.05, 0.1, 0.2 and 0.5 mm diameter yielding enhancement factors of 10-200 compared to a free space laser interaction

[en] The energy degradation of various monochromatic gamma ray sources due to self-scattering has been studied by Monte Carlo simulation techniques. A direct measurement of the energy spectrum of the ¹⁹⁸Au source used for Compton scattering experiments at the Hahn-Meitner Institute (HMI) confirms the predictions of the emission of a low energy tail. The effect of the tail on Compton profiles is examined and a method of correction is proposed and applied to measurements made at the HMI. (orig.)

[en] The [100], [110] and [111] Compton profiles have been derived from Compton scattering measurements made with 412 KeV ₁₉₈Au ν-ray sources on single-crystal samples of vanadium. These profiles and their Fourier transforms have been compared with the predictions of APW and LCAO band-structure calculations. Both sets of calculations consistently underestimate the high-momentum component of the charge density in all three directions, but overestimate the scale of the anisotropy in the momentum density distribution. An analysis of the results in terms of an elementary atomic model based on the varying occupancy of the 3d orbitals illustrates the atomic nature of the 3d band. (author)

[en] The physical principles underlying the use of gamma-ray scattering to detect composition variations in bulk alloy samples are described and the sensitivity of the method, which is an alternative to conventional transmission radiography, is evaluated for titanium alloys. The elastic (Rayleigh) and inelastic (Compton) scattered beas are beams are recorded separately and their intensities used to monitor composition changes collectively and individually. The sensitivity of the method is illustrated by measurements on titanium alloys containing aluminium and zirconium. (author)

[en] Measurements of the triple differential cross section for inelastic photon scattering from bound atomic electrons are reported. The experiment was done using 148 keV synchrotron radiation from the DORIS storage ring at DESY, Hamburg. The target was a 80 nm thin Cu foil. (author)

[en] Measurements have been made of the recoiling electron in 320 keV gamma ray inelastic scattering collisions in thin aluminium targets. The angular correlation of these electrons detected in coincidence with the scattered photon is in agreement with the kinematic requirements of the Compton effect and is correctly predicted by Monte Carlo simulations based on the impulse approximation. Further simulations of ideal-geometry experiments indicate that information about the initial electron momenta is available from an examination of those electron-photon events originating in a surface layer of one electronic mean free path depth and that elastic scattering of the recoil electrons from greater depths produces a nearly flat background to this signal. The results clearly demonstrate the feasibility of the (γ,eγ) experiment for studying electron momentum densities with synchrotron radiation. (orig.)

[en] We report coincidence measurements between inelastically scattered 148keV photons and the recoil electrons generated within a 80 nm thin Cu foil. We have analysed the Doppler broadening of the scattered photon intensity, which corresponds to a scan through the three-dimensional electron momentum density (EMD) parallel to the momentum transfer vector. The experimental data are compared with a theoretical EMD from the modified augmented plane wave method. A Monte Carlo calculation is described that allows for the correction of multiple electron scattering within the foil. Estimates of the triple-differential cross section for Compton scattering are given. The experiment was performed with the synchrotron radiation from a bending magnet of the DORIS storage ring at Deutsches Elektronen-Synchrotron (DESY), Hamburg, Federal Republic of Germany. (author)

[en] We report coincidence measurements of inelastically scattered 148 keV photons and the recoil electrons generated within thin Al and Cu foils. We have analyzed both the Doppler broadening of the scattered photon intensity and the angular correlation of the recoil electron. This corresponds to different scans through the three-dimensional electron momentum density of the target. Estimates of the triple differential cross section for Compton scattering are given. The experiment was performed with the synchrotron radiation from a bending magnet of the DORIS storage ring at DESY (Deutsches Electronen Synchrotron), Hamburg. (Author)

[en] Coincidence measurements of inelastically scattered γ-rays and the recoiling electrons for thin Al foils are reported. They demonstrate the possibility of the direct determination of the ground state electron momentum density in solids by photon-electron scattering. The experiments were performed using 144 keV synchrotron radiation from the DORIS storage ring at DESY. (author)