Corrections to the usual x-ray scattering factors in rare gases: Experiment and theory

Investigations on compton scattering: New directions

“…The ISF result of Hubbell et al (1975) included excitation channels as well as ionization and therefore includes Raman scattering, while the ''best'' predictions presented here is only for Compton scattering. However, it has been found by Young et al (2001) that the Raman contribution to total scattering is less than 1% for neon in the range 5-15 keV. Therefore, the large difference between ISF and ''best'' predictions at lower energies reflects the importance of dynamic corrections.…”

“…The availability of synchrotron sources with high resolution crystal monochromators coupled with high resolution detectors made possible precise experimental results with an uncertainty of 1-2% (Jung et al, 1998;Young et al, 2001;Southworth et al, 2000;Namito et al, 1995). All of these synchrotron measurements have been performed in order to obtain whole atom singly differential cross sections for a few elements at low photon energies (up to few tens of keVs).…”

“…The purpose of the present paper is not to present an overview of Compton scattering, but to discuss the new approaches and directions that emerged out of the recent high precision scattering experiments performed using synchrotrons (Jung et al, 1998;Young et al, 2001;Namito et al, 1995;Southworth et al, 2000) coupled with the precise theoretical predictions using S-matrix theory developed at the University of Pittsburgh. Excellent review articles on Compton scattering are available (Kane, 1992, Bergstrom andPratt, 1997;Kane, 1997).…”

Recent experimental studies of photon–atom scattering in the X-ray energy region

“…Later on, Bradley et al (1999) have reviewed the measurements of elastic scattering crosssections in the energy range 1 keV to 4 MeV available till 1999. Recently, Young et al, (2001) have reported the ratio of total X-ray scattering from Ne to that of He determined for the photon energies in the range 4-15 keV measured using synchrotron photon source. They have obtained a good agreement between the measured cross-sections and the calculated ones obtained using composite approach (Carney and Pratt, 2000).…”

Near-edge elastic photon scattering in amorphous systems

“…We consider the impact of calibration methods used in XRF, diffraction enhanced imaging (DEI) and species and environment sensitive scattering techniques such as AXS where, with increasing synchrotron brightnesses, high resolution atom and environment specific mapping is fast become a reality. While previous direct measurements of elastic scattering cross-sections have achieved high degrees of precision, either utilising gamma-ray sources scattering in solid metallic systems [2] or synchrotron light scattering in dual cells containing noble gases [3], this work focuses on the validity of the independent particle approximation (IPA) for a variety of atoms and ions embedded in amorphous systems that typify the biological context [4][5][6]. In this current work we examine Zn embedded in variety of target systems ranging from vapour deposited metallic Zn coatings on glass, in which IPA assumptions are expected to be invalid due to significant inter-atomic correlation but for which the standard tabulated data, including the binding energy for the atom, are determined; to Zn doped sol-gel glass where the structure is essentially amorphous but nearest neighbour effects are dominated by a Zn-O covalent bond; to the aqueous environment where the nearest neighbour to the Zn 2+ ion is a loosely bound oxygen through the high electronegativity associated with O in the water molecule.…”