We use published ROSAT observations of the X-ray Nova V1974 Cygni 1992 to test a model for interstellar dust, consisting of a mixture of carbonaceous grains and silicate grains. The time-dependent X-ray emission from the nova is modelled as the sum of emission from a ONe white dwarf plus a thermal plasma, and X-ray scattering is calculated for a dust mixture with a realistic size distribution. ...

the internal structure of dna-ctab and dna-ddab is investigated by a small angel x- ray scattering(saxs) instrument. hexagonal packing of dna was observed for dna complex with ctab, and for ddabcomplex is observed lamellar structure. variations in the internal spacing and degree of long-range ordering aredependent on both surfactant type and concentrations of added salt. when we increased the a...

Dark-field images are formed from x-ray small-angle scattering signals. The small-angle scattering signals are particularly sensitive to structural variation and density fluctuation on a length scale of several tens to hundreds of nanometers, offering a unique contrast mechanism to reveal subtle structural features of an object. In this study, based on the principle of energy conservation, we d...

A femtosecond X-ray source was developed by Thomson scattering through interaction between a lowemittance picosecond electron beam and a terawatt femtosecond laser light at 90 configuration. The observed X-ray intensity with peak energy of 2.3 keV and pulse duration of 270 fs rms was typically 1.4x10 photons/pulse. The pulse-to-pulse fluctuation of the X-ray intensity was measured to be 25%. Th...

We report here a multiple-reflection type ultra-small-angle x-ray-scattering apparatus constructed according to the principle proposed by Bonse and Hart. The ultra-small-angle x-ray scattering technique enables us to investigate the distribution of solutes or particles in turbid systems, which could not be studied by the conventional light-scattering and microscopic methods. By this method, the...

We report a comparison of high resolution inelastic x-ray Brillouin scattering to coherent inelastic neutron scattering for amorphous deuterated polybutadiene, done for one temperature in the glass phase and another one in the melt. The x-ray scattering proves to be by far the better technique for such a polymer within its present resolution bounds. The neutron scattering allows one to extend t...

We present theoretical calculations of the X-ray scattering properties of porous grain aggregates with olivine monomers. The small and large angle scattering properties of these aggregates are governed by the global structure and substructure of the grain, respectively. We construct two diagnostics, RX and TX, based on the optical and X-ray properties of the aggregates, and apply them to a Chan...

Single crystals of ice Ih, extracted from the subglacial Lake Vostok accretion ice layer (3621 m depth) were investigated by means of diffuse x-ray scattering and inelastic x-ray scattering. The diffuse scattering was identified as mainly inelastic and rationalized in the frame of ab initio calculations for the ordered ice XI approximant. Together with Monte-Carlo modelling, our data allowed re...

The atomic structure and the chemical composition of buried interfaces is of high interest for many applications e.g. in multilayered samples such as oxidized metals, optic or microelectronic devices. Conventional surface analytical techniques such as X-ray photoelectron spectroscopy (XPS), Auger-electron spectroscopy (AES) or ion scattering spectroscopy (ISS) have an extremely high surface sen...

Introduction: The basis of image formation in Computed Tomography (CT) lies in the x-ray linear attenuation coefficient of the scanned material. Compton scattering and photoelectric effect are the dominant interactions of the x-ray photons with the subject, in the range of diagnostic radiology. These two coefficients are important in tissue characterization by Dual-Energy CT (D...