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Die zwölfte Konferenz des Forschungskreises Vereinte Nationen wurde am 28. Juni 2014 an der Universität Potsdam veranstaltet und stand unter dem Thema „Konzepte für die Reform der Vereinten Nationen“. Dabei wurde das komplexe Verhältnis zwischen Reformnotwendigkeit und Machbarkeitserwartungen einerseits und ausgebliebenen weitreichenden Strukturreformen und erfolgten „kleineren“, pragmatischen Reformschritten andererseits deutlich. Mit den vier Referaten stellte die Konferenz in der Tradition der Potsdamer UNO-Konferenzen die Verbindung von Wissenschaft und Praxis unter Beteiligung unterschiedlicher Disziplinen her.
Mit der Broschüre soll allen Interessierten die Möglichkeit gegeben werden, Einblick in ausgewählte Schwerpunkte der Reformdiskussion zu erhalten:
An ein Grundsatzreferat zu bisherigen Reformprozessen im UN-System insgesamt schließen sich drei Texte an, die das Verhältnis zwischen den Vereinten Nationen und den nichtstaatlichen Akteuren in den Blick nehmen, die relativ neue Institution des Menschenrechtsrates als Teil der Reformbemühungen betrachten und schließlich Ergebnisse und Trends bei den Reformen der Arbeitsmethoden des Sicherheitsrates erörtern.
Introducing the CTA concept
(2013)
The Cherenkov Telescope Array (CTA) is a new observatory for very high-energy (VHE) gamma rays. CTA has ambitions science goals, for which it is necessary to achieve full-sky coverage, to improve the sensitivity by about an order of magnitude, to span about four decades of energy, from a few tens of GeV to above 100 TeV with enhanced angular and energy resolutions over existing VHE gamma-ray observatories. An international collaboration has formed with more than 1000 members from 27 countries in Europe, Asia, Africa and North and South America. In 2010 the CTA Consortium completed a Design Study and started a three-year Preparatory Phase which leads to production readiness of CTA in 2014. In this paper we introduce the science goals and the concept of CTA, and provide an overview of the project.
This is the first of a series of papers presenting the results from our survey of 25 Galactic globular clusters with the MUSE integral-field spectrograph. In combination with our dedicated algorithm for source deblending, MUSE provides unique multiplex capabilities in crowded stellar fields and allows us to acquire samples of up to 20 000 stars within the half-light radius of each cluster. The present paper focuses on the analysis of the internal dynamics of 22 out of the 25 clusters, using about 500 000 spectra of 200 000 individual stars. Thanks to the large stellar samples per cluster, we are able to perform a detailed analysis of the central rotation and dispersion fields using both radial profiles and two-dimensional maps. The velocity dispersion profiles we derive show a good general agreement with existing radial velocity studies but typically reach closer to the cluster centres. By comparison with proper motion data, we derive or update the dynamical distance estimates to 14 clusters. Compared to previous dynamical distance estimates for 47 Tuc, our value is in much better agreement with other methods. We further find significant (>3 sigma) rotation in the majority (13/22) of our clusters. Our analysis seems to confirm earlier findings of a link between rotation and the ellipticities of globular clusters. In addition, we find a correlation between the strengths of internal rotation and the relaxation times of the clusters, suggesting that the central rotation fields are relics of the cluster formation that are gradually dissipated via two-body relaxation.