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In this study, we analyze the recently proposed charge transfer fluctuations within a finite pseudo-rapidity space. As the charge transfer fluctuation is a measure of the local charge correlation length, it is capable of detecting inhomogeneity in the hot and dense matter created by heavy ion collisions. We predict that going from peripheral to central collisions, the charge transfer fluctuations at midrapidity should decrease substantially while the charge transfer fluctuations at the edges of the observation window should decrease by a small amount. These are consequences of having a strongly inhomogeneous matter where the QGP component is concentrated around midrapidity. We also show how to constrain the values of the charge correlations lengths in both the hadronic phase and the QGP phase using the charge transfer fluctuations.
Within the ADD-model, we elaborate an idea by Vacavant and Hinchliffe and show quantitatively how to determine the fundamental scale of TeV-gravity and the number of compactified extra dimensions from data at LHC. We demonstrate that the ADD-model leads to strong correlations between the missing E_T in gravitons at different center of mass energies. This correlation puts strong constraints on this model for extra dimensions, if probed at sqr s=5.5 TeV and sqrt s=14 TeV at LHC.
Der Autor beschäftigt sich u. a. mit den Fragen: Welchen Stellenwert haben unsere literarischen Bildungsgüter in der Mediengesellschaft? Stehen Goethe und Schiller, das Dioskurenpaar der deutschen Klassik, noch fest auf dem Weimarer Sockel, oder zerbröselt dieser zum Sanierungsfall, en passant besucht auf Klassenfahrten, von denen nur das ins heimische Bücherregal wandert, was leicht faßlich ist?
In regionalen Schweizer Chaträumen stellt die Mundart mit Anteilen um 80% bis 90% die unmarkierte Varietät dar. Chats bieten somit einen Einblick in die individuell geprägte Verschriftung der Schweizer Dialekte, die sich einerseits regional verschieden präsentiert und andererseits fern von Vereinheitlichungstendenzen liegt. Durch diese Normierungsferne lässt sich aus den Chatdaten in groben Zügen eine Sprachgeographie nachzeichnen, wie sie im Sprachatlas der deutschen Schweiz SDS (1962–1997) festgehalten ist. Hier sollen Reflexe der sprachgeographischen Verteilung in der Verschriftung der flektierten Formen von «haben» nachgezeichnet werden. Neben der grundsätzlichen Bestätigung dieser Struktur zeigen sich in der Analyse auch systematisch Abweichungen, die unter Berücksichtigung der Verschriftungsbarriere Hinweise auf Sprachwandel geben können, die jedoch mit authentischen Daten gesprochener Sprache überprüft werden müssen.
Die Prosodie der Mundarten wurde schon früh als auffälliges und distinktes Merkmal wahrgenommen und in mehreren Arbeiten zur Grammatik des Schweizerdeutschen mittels Musiknoten festgehalten (u. a. J. Vetsch 1910, E. Wipf 1910, K. Schmid 1915, W. Clauss 1927, A. Weber 1948), wobei schon A. Weber (1948, S. 53) anmerkt, "dass sich der musikalische Gang der Rede nicht ohne Gewaltsamkeit mit der üblichen Notenschrift darstellen lässt". Da also eine adäquate Kodierung, eine theoretische Grundlage und die notwendigen phonetischen Instrumente zur Intonationsforschung fehlten, wurden diese ersten Ansätze nicht aus- und weitergeführt. Erst in der Mitte des 20. Jahrhunderts brachte die technische Entwicklung Instrumente zur Messung der Prosodie hervor, die nun durch die Popularisierung der entsprechenden Computerprogramme im Übergang zum 21. Jahrhundert für die linguistische Forschung intensiv und breit genutzt werden können.
It is investigated whether canonical suppression associated with the exact conservation of an U(1)-charge can be reproduced correctly by current transport models. Therefore a pion-gas having a volume-limited cross section for kaon production and annihilation is simulated within two different transport prescriptions for realizing the inelastic collisions. It is found that both models can indeed dynamically account for the canonical suppression in the yields of rare strange particles.
We study the effects of isovector-scalar meson delta on the equation of state (EOS) of neutron star matter in strong magnetic fields. The EOS of neutron-star matter and nucleon effective masses are calculated in the framework of Lagrangian field theory, which is solved within the mean-field approximation. From the numerical results one can find that the delta-field leads to a remarkable splitting of proton and neutron effective masses. The strength of delta-field decreases with the increasing of the magnetic field and is little at ultrastrong field. The proton effective mass is highly influenced by magnetic fields, while the effect of magnetic fields on the neutron effective mass is negligible. The EOS turns out to be stiffer at B < 10^15G but becomes softer at stronger magnetic field after including the delta-field. The AMM terms can affect the system merely at ultrastrong magnetic field(B > 10^19G). In the range of 10^15 G - 10^18 G the properties of neutron-star matter are found to be similar with those without magnetic fields.
The cumulant method is applied to study elliptic flow (v_2) in Au+Au collisions at sqrt s=200 AGeV, with the UrQMD model. In this approach, the true event plane is known and both the non-flow effects and event-by-event spatial (epsilon) and v_2 fluctuations exist. Qualitatively, the hierarchy of v_2 's from two, four and six-particle cumulants is consistent with the STAR data, however, the magnitude of v_2 in the UrQMD model is only 60% of the data. We find that the four and six-particle cumulants are good measures of the real elliptic flow over a wide range of centralities except for the most central and very peripheral events. There the cumulant method is affected by the v_2 fluctuations. In mid-central collisions, the four and six-particle cumulants are shown to give a good estimation of the true differential v_2, especially at large transverse momentum, where the two-particle cumulant method is heavily affected by the non-flow effects.
We present a detailed study of chemical freeze-out in p-p, C-C, Si-Si and Pb-Pb collisions at beam momenta of 158A GeV as well as Pb-Pb collisions at beam momenta of 20A, 30A, 40A and 80A GeV. By analyzing hadronic multiplicities within the statistical hadronization model, we have studied the parameters of the source as a function of the number of the participating nucleons and the beam energy. We observe a nice smooth behaviour of temperature, baryon chemical potential and strangeness under-saturation parameter as a function of energy and nucleus size. Interpolating formulas are provided which allow to predict the chemical freeze-out parameters in central collisions at centre-of-mass energies > 4.5 GeV and for any colliding ions. Specific discrepancies between data and model emerge in particle ratios in Pb-Pb collisions at SPS between 20A and 40A GeV of beam energy which cannot be accounted for in the considered model schemes.