Performance studies of the final prototype for the CASTOR forward calorimeter at the CMS experiment

We present performance results of the final prototype for the CASTOR quartz-tungsten sampling calorimeter, to be installed in the very forward region of the CMS experiment at the LHC. The energy linearity and resolution, the uniformity, as well as the spatial resolution of the prototype to electromagnetic and hadronic showers are studied with $E=$ 10--200 GeV electrons, $E=$ 20--350 GeV pions, and $E=$ 50, 150 GeV muons in beam tests carried out at CERN/SPS in 2007

Quantitative analysis of gold nanoparticles from synchrotron data by means of least-squares techniques

Powder samples of thiol-capped gold nanoparticles in the size range of 2-4 nm were quantitatively characterized by means of synchrotron X-ray diffraction data, with respect to their structure, size and strain distributions. A novel Rietveld-like approach was applied, refining domain size distribution, strain-size dependence and structure type concentrations. Three structure types (cuboctahedron, icosahedron, decahedron) were considered in this analysis and a detail study of the strain content was performed by comparing different models. The results showed a strong influence of the strain model and a careful analysis is presented. Final domain size and strain distributions agree well with the existence of both single-domain and imperfectly formed or multi-domain nanoparticles, but the final strain profiles seem to be mostly related to the different degree of structural perfection at different sizes as a result of the synthesis process. The present work represents an important step towards the development of robust methods to determine strain profiles in nanosystems, aiming to fulfill the description of these important but complex systems. Copyright Springer-Verlag Berlin/Heidelberg 2004