We analyze the 0.5−10 keV spectra of six Seyfert 2 galaxies observed with the X-ray satellite ASCA: Mrk 3, Mrk 348, Mrk 1210, Mrk 477, NGC 7212, and Was 49b. These galaxies were selected based on their possession of optical polarized broad lines. In the 2−10 keV band, their spectra are heavily absorbed, with 2−10 keV absorption-corrected X-ray luminosities ranging from 10 to 10 ergs s−1. The ob...

The present thesis is devoted to theoretical studies of resonant X-ray scattering and propagation of strong X-ray pulses. In the first part of the thesis the nuclear dynamics of different molecules is studied using resonant X-ray Raman and resonant Auger scattering techniques. We show that the shortening of the scattering duration by the detuning results in a purification of the Raman spectra f...

Counterion atmospheres condensed onto charged biopolymers strongly affect their physical properties and biological functions, but have been difficult to quantify experimentally. Here, monovalent and divalent counterion atmospheres around DNA double helices in solution are probed using small-angle x-ray scattering techniques. Modulation of the ion scattering factors by anomalous (resonant) x-ray...

The problem of reconstructing the charge density of a non-periodic sample from its diffuse X-ray scattering is considered. For a sample known to be isolated, an artificial superlattice may be assumed and the numerical direct methods of crystallography applied to the continuous distribution of diffuse scattering in order to solve the phase problem. This method is applied to simulated soft-X-ray ...

The resonant-scattering contributions to single-crystal X-ray diffraction data enable the absolute structure of crystalline materials to be determined. Crystal structures can be determined even if they contain considerably disordered regions because a correction is available via a discrete Fourier transform of the residual electron density to approximate the X-ray scattering from the disordered...

2014 A stopped-flow apparatus and control system, designed for the study of rapid reaction kinetics in solution by X-ray scattering, is described. Inspired from a commercial stopped-flow unit used with UV and visible light, the X-ray device has a dead-time of 80 ms. Results are presented for the polymerization of the coat protein of Brome mosaic virus following a pH jump, using a small angle X-...

Small-angle x-ray scattering (SAXS) imaging can differentiate tissue types based on their nanoscale molecular structure. However, characterization of the coherent scattering cross-section profile of relevant tissues is needed to optimally design SAXS imaging techniques for a variety of biomedical applications. Reported measured nervous tissue x-ray scattering cross sections under a synchrotron ...

Non-resonant inelastic x-ray scattering can provide information on various atomic-scale properties and phenomena by probing the spectrum of electronic excitations. The technique allows bulk-sensitive measurements and relatively freely tunable sample conditions even for excitations with energies in the soft x-ray range. Also non-dipolar excitations are accessible by virtue of the ability to impo...

We consider the multidimensional Newton-Einstein equation in static electromagnetic field ṗ = F (x, ẋ), F (x, ẋ) = −∇V (x) + 1 c B(x)ẋ, p = ẋ √ 1− |ẋ|2 c2 , ṗ = dp dt , ẋ = dx dt , x ∈ C(R,R), (∗) where V ∈ C2(R,R), B(x) is the d× d real antisymmetric matrix with elements Bi,k(x) = ∂ ∂xi Ak(x)− ∂ ∂xkAi(x), and |∂ j xAi(x)|+ |∂j xV (x)| ≤ β|j|(1 + |x|)−(α+|j|) for x ∈ R, |j| ≤ 2, i = 1..d and so...