Refine
Year of publication
Document Type
- Article (30828) (remove)
Language
- English (15926)
- German (13032)
- Portuguese (584)
- French (385)
- Croatian (251)
- Spanish (242)
- Italian (132)
- Turkish (101)
- Latin (35)
- Multiple languages (35)
Has Fulltext
- yes (30828)
Is part of the Bibliography
- no (30828) (remove)
Keywords
- Deutsch (482)
- taxonomy (451)
- Literatur (282)
- new species (196)
- Hofmannsthal, Hugo von (184)
- Rezeption (155)
- Filmmusik (154)
- Übersetzung (135)
- Vormärz (117)
- Johann Wolfgang von Goethe (107)
Institute
- Medizin (5419)
- Physik (1983)
- Biowissenschaften (1153)
- Biochemie und Chemie (1113)
- Extern (1069)
- Gesellschaftswissenschaften (803)
- Frankfurt Institute for Advanced Studies (FIAS) (755)
- Geowissenschaften (593)
- Präsidium (453)
- Philosophie (448)
A generic property of a first-order phase transition in equilibrium, and in the limit of large entropy per unit of conserved charge, is the smallness of the isentropic speed of sound in the mixed phase . A specific prediction is that this should lead to a non-isotropic momentum distribution of nucleons in the reaction plane (for energies < 40A GeV in our model calculation). On the other hand, we show that from present effective theories for low-energy QCD one does not expect the thermal transition rate between various states of the effective potential to be much larger than the expansion rate, questioning the applicability of the idealized Maxwell/Gibbs construction. Experimental data could soon provide essential information on the dynamics of the phase transition.
The flying geese model, a theory of industrial development in latecomer economies, was developed in the 1930s by the Japanese economist Akamatsu Kaname (1896–1974). While rarely known in western countries, it is highly prominent in Japan and seen as the main economic theory underlying Japan’s economic assistance to developing countries. Akamatsu’s original interpretation of the flying geese model differs fundamentally from theories of western origin, such as the neoclassical model and Raymond Vernon’s product cycle theory. These differences include the roles of factors and linkages in economic development, the effects of demand and supply, as well as the dynamic and dialectical character of Akamatsu’s thinking. Later reformulations of the flying geese model, pioneered by Kojima Kiyoshi, attempt to combine aspects of Akamatsu’s theory with neoclassical thinking. This can be described as the “westernization” of the flying geese model. It is this reformulated interpretation that has become popular in Japan’s political discourse, a process that might be explained by the change in Japan’s perspective from that of a developing to that of an advanced economy. The position taken by Japan in its recent controversy with the World Bank, however, shows that many basic elements of Akamatsu’s thinking are still highly influential within both Japan’s academia and its government and are therefore relevant for understanding current debates on development theory.
The lightest supersymmetric particle, most likely the neutralino, might account for a large fraction of dark matter in the Universe.We show that the primordial spectrum of density fluctuations in neutralino cold dark matter (CDM) has a sharp cut-off due to two damping mechanisms: collisional damping during the kinetic decoupling of the neutralinos at (10 MeV) and free streaming after last scattering of neutralinos. The cut-off in the primordial spectrum defines a minimal mass for CDM objects in hierarchical structure formation. For typical neutralino and sfermion masses the first gravitionally bound neutralino clouds have masses above 10 -6 M .
We study the bound states of anti-nucleons emerging from the lower continuum in finite nuclei within the relativistic Hartree approach including the contributions of the Dirac sea to the source terms of the meson fields. The Dirac equation is reduced to two Schr¨odinger-equivalent equations for the nucleon and the anti-nucleon respectively. These two equations are solved simultaneously in an iteration procedure. Numerical results show that the bound levels of anti-nucleons vary drastically when the vacuum contributions are taken into account. PACS number(s): 21.10.-k; 21.60.-n; 03.65.Pm
Recent progress in the understanding of the high density phase of neutron stars advances the view that a substantial fraction of the matter consists of hyperons. The possible impacts of a highly attractive interaction between hyperons on the properties of compact stars are investigated.We find that a hadronic equation of state with hyperons allows for a first order phase transition to hyperonic matter. The corresponding hyperon stars can have rather small radii of R 8 km.
The production of black holes at Tevatron and LHC in spacetimes with compactified space-like large extra dimensions is studied. Either black holes can already be observed in ¯ pp collisions at s = 1.8 TeV or the fundamental gravity scale has to be above 1.4 TeV. At LHC the creation of a large number of quasi-stable black holes is predicted, with lifetimes beyond several hundred fm/c. A cut-off in the high-PT jet cross section is shown to be a unique signature of black hole production. This signal is compared to the jet plus missing energy signature due to graviton production in the final state as proposed by the ATLAS collaboration.
Abstract Geant4 is a toolkit for simulating the passage of particles through matter. It includes a complete range of functionality including tracking, geometry, physics models and hits. The physics processes offered cover a comprehensive range, including electromagnetic, hadronic and optical processes, a large set of long-lived particles, materials and elements, over a wide energy range starting, in some cases, from 250 eV and extending in others to the TeV energy range. It has been designed and constructed to expose the physics models utilised, to handle complex geometries, and to enable its easy adaptation for optimal use in different sets of applications. The toolkit is the result of a worldwide collaboration of physicists and software engineers. It has been created exploiting software engineering and object-oriented technology and implemented in the C++ programming language. It has been used in applications in particle physics, nuclear physics, accelerator design, space engineering and medical physics. PACS: 07.05.Tp; 13; 23
The amount of proton stopping in central Pb+Pb collisions from 20–160 A GeV as well as hyperon and antihyperon rapidity distributions are calculated within the UrQMD model in comparison to experimental data at 40, 80, and 160 A GeV taken recently from the NA49 collaboration. Furthermore, the amount of baryon stopping at 160A GeV for Pb+Pb collisions is studied as a function of centrality in comparison to the NA49 data. We find that the strange baryon yield is reasonably described for central collisions, however, the rapidity distributions are somewhat more narrow than the data. Moreover, the experimental antihyperon rapidity distributions at 40, 80, and 160 A GeV are underestimated by up to factors of 3—depending on the annihilation cross section employed—which might be addressed to missing multimeson fusion channels in the UrQMD model. Pacs-Nr.: 25.75.2q, 24.10.Jv, 24.10.Lx
Accelerating cavities exchange HOM power through interconnecting beam pipes in case of signal frequencies above the cut-off of their propagating waveguide modes. This may lead either to improved HOM damping or - in the case most severe - to unwanted phase coherence of fields to the beam. Therefore the knowledge of the scattering properties of a cavity as a line element is needed to analyse all kinds of RF cavity-cavity interaction. Since there is a lack of measurement tools capable to provide a multidimensional scattering matrix at a given frequency point, we have been developing a method for this purpose. It uses a set of 2-port S-parameters of the device under test, embedded in a number of geometrically different RF environments. The application of the method is demonstrated with copper models of TESLA cavities.