Gluon propagator in diffractive scattering

In this work, we perform a comparison of the employ of distinct gluon propagators with the experimental data in diffractive processes, $pp$ elastic scattering and light meson photo-production. The gluon propagators are calculated through non-perturbative methods, being justified their use in this class of events, due to the smallness of the momentum transfer. Our results are not able to select the best choice for the modified gluon propagator among the analyzed ones, showing that the application of this procedure in this class of high energy processes, although giving a reasonable fit to the experimental data, should be taken with same caution.Comment: 14 pages, 4 figures, accepted for publication in Int. J. Mod. Phys. A (uses ws-ijmpa.cls). Authors correcte

The Quadrupole Resonator, Design Considerations and Layout of a New Instrument for the RF Characterization of Superconducting Surface Samples

A disk-shaped superconducting sample is welded onto an Nb support cylinder and exposed to the magnetic RF field of a four-wire transmission line resonator. The fields on the cylinder wall decay in a c ut-off like fashion in such a way that they perturb the measurement very little. RF dissipation of the disk is determined by substitution with a d.c. heater on the back of the sample which is made to produce the same temperature rise, controlled by thermometers

Normative coherence for development : What relevance for responsive regionalism?

Motivation The Sustainable Development Goals (SDGs) call for transformative development rooted in international norms, such as human rights, rule of law and gender equality. Often, however, nation-states do not implement these norms to the extent to which they are envisaged. Against this backdrop, regions have the potential to fill this implementation vacuum. Purpose Without a normative dimension, transformative development risks reproducing traditional economic development. In this special issue we focus on norm implementation in different world regions through the lens of normative coherence for development. Methods and approach The articles in this special issue all use qualitative methods, such as text analysis and in-depth interviews. Given the different regional contexts, each article has its own approach to normative coherence for development depending on the regional normative framework. Findings This special issue indicates that regions are an important interlocutor between the global, national, and sub-national level and, as such, are crucial for implementing the sustainable development agenda. The articles show, however, that to date normative coherence for development has not been achieved due to overriding priorities and technical approaches to policy coherence for development. Policy implications With this special issue we aim to draw more attention to the topic of normative coherence for development and show that policies need to be adjusted in order to reflect the normative dimension of sustainable development.Peer reviewe

Normative Policy Coherence for Development in the EU

In this research the application of values in development policies is compared to the application of values in trade policies. As the EU is the defender of European values, it is expected that the EU and its member states apply these values coherently over different policy arenas. Germany and the Netherlands are the two member states representing the EU. The United States and Japan represent non-European countries. Those four countries are compared in their development and trade policies towards Vietnam. Commission Annual Reports, OECD Peer Reviews and additional national documents on development and trade are the basis for this analysis. In addition, political statements and related publication are included for the study of values. This study shows that the EU member states apply European values in the field of development policies. Japan and the US do not apply values in either of the policy arenas

The quadrupole resonator: Construction, RF System Field Calculations and First Applications

The quadrupole resonator allows measurement of the RF properties of superconducting (sc) films deposited on disk-shaped metallic substrates. We describe the construction of the apparatus, the brazing and electron-beam welding procedures, the arrangements for compensating mechanical tolerances of samples and for assuring reproducible sample illumination. We explain the special features of the RF sy stem and give the results of field calculations with a 3D cavity code. Finally we present first measurements of Nb on Cu film samples and compare them with calibrations done with a bulk Nb sample

Non-perturbative gluons in diffractive photo-production of J/Psi

The modifications induced in the calculation of the cross section of the diffractive process gamma gamma -> J/Psi J/Psi when the gluon propagator is changed are analyzed. Instead of the usual perturbative gluon propagator, alternative forms obtained using non-perturbative methods like Dyson-Schwinger equations are used to consider in a more consistent way the contributions of the infrared region. The result shows a reduction in the differential cross-section for low momentum transfer once compared with the perturbative result, to be confirmed with future experimental results from TESLA.Comment: 17 pages, 5 figures, RevTex, Accepted for publication in Phys. Lett.

Estimation of mass thickness response of embedded aggregated silica nanospheres from high angle annular dark-field scanning transmission electron micrographs

In this study we investigate the functional behavior of the intensity in high-angle annular dark field (HAADF) scanning transmission electron micrograph (STEM) images. The model material is a silica particle (20 nm) gel at 5 wt%. By assuming that the intensity response is monotonically increasing with increasing mass thickness of silica, an estimate of the functional form is calculated using a maximum likelihood approach. We conclude that a linear functional form of the intensity provides a fair estimate but that a power function is significantly better for estimating the amount of silica in the z-direction. The work adds to the development of quantifying material properties from electron micrographs, especially in the field of tomography methods and three-dimensional quantitative structural characterization from a STEM micrograph. It also provides means for direct three-dimensional quantitative structural characterization from a STEM micrograph