Spectral distortion of cosmic background radiation by scattering on hot electrons. Exact calculations

The spectral distortion of the cosmic background radiation produced by the inverse Compton scattering on hot electrons in clusters of galaxies (thermal Sunyaev-Zeldovich effect) is calculated for arbitrary optical depth and electron temperature. The distortion is found by a numerical solution of the exact Boltzmann equation for the photon distribution function. In the limit of small optical depth and low electron temperature our results confirm the previous analyses. In the opposite limits, our method is the only one that permits to make accurate calculations.Comment: 18 pages, 7 figures, to be published in Ap

Adsorption preference reversal phenomenon from multisite-occupancy theory fortwo-dimensional lattices

The statistical thermodynamics of polyatomic species mixtures adsorbed on two-dimensional substrates was developed on a generalization in the spirit of the lattice-gas model and the classical Guggenheim-DiMarzio approximation. In this scheme, the coverage and temperature dependence of the Helmholtz free energy and chemical potential are given. The formalism leads to the exact statistical thermodynamics of binary mixtures adsorbed in one dimension, provides a close approximation for two-dimensional systems accounting multisite occupancy and allows to discuss the dimensionality and lattice structure effects on the known phenomenon of adsorption preference reversal.Comment: 13 pages, 4 figure

Lepton Flavour Violation in a Left-Right Symmetric Model

We consider in this paper a Left-Right symmetric gauge model in which a global lepton-number-like symmetry is introduced and broken spontaneously at a scale that could be as low as 10^4 GeV or so. The corresponding physical Nambu-Goldstone boson, which we call majoron and denote J, can have tree-level flavour-violating couplings to the charged fermions, leading to sizeable majoron-emitting lepton-flavour-violating weak decays. We consider explicitly a leptonic variant of the model and show that the branching ratios for \mu -> e+J, \tau -> e + J and \tau -> \mu + J decays can be large enough to fall within the sensitivities of future \mu and \tau factories. On the other hand the left-right gauge symmetry breaking scale may be as low as few TeV.Comment: LaTeX, 16 pages, 3 PS figures, uses JHEP.cls, published versio

The effect of the lateral interactions on the critical behavior of long straight rigid rods on two-dimensional lattices

Using Monte Carlo simulations and finite-size scaling analysis, the critical behavior of attractive rigid rods of length k (k-mers) on square lattices at intermediate density has been studied. A nematic phase, characterized by a big domain of parallel k-mers, was found. This ordered phase is separated from the isotropic state by a continuous transition occurring at a intermediate density \theta_c, which increases linearly with the magnitude of the lateral interactions.Comment: 7 pages, 6 figure

Transformative landscapes: liminality and visitors’ emotional experiences at German memorial sites

The atrocities of Nazi Germany included the radical transformation of natural landscapes. At Ravensbrück (Brandenburg), a lakeside setting became the site of the largest women’s concentration camp in Germany, processing approximately 159,000 inmates until 1945. Similarly, at Flossenbürg (Bavaria), a picturesque valley in the Oberpfälzer Wald housed a large concentration camp with approximately 100,000 inmates over seven years and a granite quarry to support Hitler’s extensive construction programme. After the war, part of Ravensbrück became a Soviet Army base, while large sections of Flossenbürg were removed to make way for a new housing and industrial development. Along with other former camps (particularly Auschwitz-Birkenau), parts of these landscapes were developed into memorial sites that aim to provide a liminal experience for visitors – a ‘rite of passage’. In attempting to regain a sense of place that evokes the trauma of the past, the landscapes of the memorial sites of Ravensbrück and Flossenbürg were recently altered to resemble their appearance in 1945. For visitors, however, the aesthetic experience of these landscapes lies in stark contrast to the narrative they encounter at both sites; they are surprised to see signs of life, objecting to modernisation at Ravensbrück or the existence of a supermarket next to the memorial site in Flossenbürg. This paper examines the transformative processes of these landscapes and explores how their liminality is constructed, experienced and challenged. Through empirical visitor research conducted at both sites, it provides a critical evaluation of the narrative given to visitors and suggests how these important sites can offer a more engaging ‘rite of passage’

Percolation in Hierarchical Scale-Free Nets

We study the percolation phase transition in hierarchical scale-free nets. Depending on the method of construction, the nets can be fractal or small-world (the diameter grows either algebraically or logarithmically with the net size), assortative or disassortative (a measure of the tendency of like-degree nodes to be connected to one another), or possess various degrees of clustering. The percolation phase transition can be analyzed exactly in all these cases, due to the self-similar structure of the hierarchical nets. We find different types of criticality, illustrating the crucial effect of other structural properties besides the scale-free degree distribution of the nets.Comment: 9 Pages, 11 figures. References added and minor corrections to manuscript. In pres