X-ray photon correlation spectroscopy during homogenous shear flow

Multi-speckle X-ray photon correlation spectroscopy in the ultra-small-angle X-ray scattering range

Multi-speckle X-ray photon correlation spectroscopy (XPCS) measurements in the ultra-small-angle range are performed using a long pinhole collimation instrument in combination with two-dimensional photon-counting and high-sensitivity imaging detectors. The feasibility of the presented setup to measure dynamics on different time and length scales pertinent to colloidal systems is shown. This set...

Indirectly illuminated X-ray area detector for X-ray photon correlation spectroscopy.

An indirectly illuminated X-ray area detector is employed for X-ray photon correlation spectroscopy (XPCS). The detector consists of a phosphor screen, an image intensifier (microchannel plate), a coupling lens and either a CCD or CMOS image sensor. By changing the gain of the image intensifier, both photon-counting and integrating measurements can be performed. Speckle patterns with a high sig...

X-ray Correlation Spectroscopy Instrument

On the use of two-time correlation functions for X-ray photon correlation spectroscopy data analysis

Multi-time correlation functions are especially well suited to study non-equilibrium processes. In particular, two-time correlation functions are widely used in X-ray photon correlation experiments on systems out of equilibrium. One-time correlations are often extracted from two-time correlation functions at different sample ages. However, this way of analysing two-time correlation functions is...

Investigation of q-dependent dynamical heterogeneity in a colloidal gel by x-ray photon correlation spectroscopy.

We use time-resolved x-ray photon correlation spectroscopy to investigate the slow dynamics of colloidal gels made of moderately attractive carbon black particles. We show that the slow dynamics is temporally heterogeneous and quantify its fluctuations by measuring the variance chi of the instantaneous intensity correlation function. The amplitude of dynamical fluctuations has a nonmonotonic de...