Cross sections for multi-particle final states at a linear collider

In this paper total cross sections for signals and backgrounds of top- and Higgs-production channels in e ⁺ e^- collisions at a future linear collider are presented. All channels considered are characterized by the emergence of six-particle final states. The calculation takes into account the full set of tree-level amplitudes in each process. Two multi-purpose parton level generators, HELAC/PHEGAS and AMEGIC + + , are used, and their results are found to be in perfect agreement.Received: 26 November 2003, Revised: 15 January 2004, Published online: 3 March 2004     

The Rate Constant for Dissociative Electron Attachment to Ozone Revisited

The rate constant for dissociative electron attachment to ozone has been derived over the energy range from about 0 to 10 eV using recently measured and also corrected cross section data. The new rate constant data sets for two partial dissociative channels, as well as for the total dissociative electron attachment, are compared with previously reported values, and existing discrepancies are discussed.     

Quantification of Secondary Fe-Phases Formed During Sorption Experiments on Chlorites

Hyperfine Interactions - During batch sorption experiments of heavy metals on chlorite not only sorption reactions take place, but also reactions of chemical weathering leading to mineral...     

Introduction to Hardy Spaces

Basic material from the theory of Hardy spaces is presented. The principle of positive energy representations is used as motivation to introduce these spaces.     

Pattern forming precipitation in gels due to coupling of chemical reactions with diffusion

Precipitate-forming chemical reactions have been studied in chemically cross-linked poly(vinyl alcohol) gel medium. One of the reactive components was incorporated into the gel, the other was allowed to diffuse into it. Depending on the experimental conditions the reaction-diffusion process often results in patterns of different type. Experiments performed in tubes and in thin layers were carried out in order to investigate the effects of various factors (cross-linking density, swelling degree as well as the concentrations of the outer and inner electrolytes) on the morphologies of the precipitate patterns. It was found that precipitation occurs not only in the Liesegang bands, but also between bands. Beside Liesegang-type structures, tree-like patterns have been observed, showing a characteristic periodicity in the density profile obtained by digitalized image analyses.     

Fluctuation measurements in a supersonic boundary layer implying in-situ calibration of the hot-wire anemometer

A calibration technique for the constant-temperature hot-wire anemometer is presented, which is based on traversing the probe through the boundary layer of a flat plate while simultaneously performing fluctuation measurements. The free stream Mach number was M = 2.54, and the Reynolds number Re_d, based on wire diameter, ranged from 9 to 23. A comparison of the sensitivity values obtained with the aid of such a calibration procedure — under the condition of neglecting low temperature loadings (t<0.6) — agrees well with sensitivities determined with free-stream data-The use of a modified transfer function for correcting the power spectra of flow perturbations revealed a conformity of wide parts of the corrected spectra with the Kolmogorov decay. The fluctuation levels of total temperature and mass flux were computed for the boundary layer of a flat plate. This work was presented at the International Conference on the Methods of Aerophysical Research ICMAR 2007, which was held in Novosibirsk on 5–10 February 2007.     

Reducing system of parameters and the Cohen-Macaulay property

Let R be a local ring and let (x ₁, …, x _r) be part of a system of parameters of a finitely generated R-module M, where r < dim_R M. We will show that if (y ₁, …, y _r) is part of a reducing system of parameters of M with (y ₁, …, y _r) M = (x ₁, …, x _r) M then (x ₁, …, x _r) is already reducing. Moreover, there is such a part of a reducing system of parameters of M iff for all primes P ε Supp M ∩ V _R(x ₁, …, x _r) with dim_R R/P = dim_R M − r the localization M _P of M at P is an r-dimensional Cohen-Macaulay module over R _P. Furthermore, we will show that M is a Cohen-Macaulay module iff y _d is a non zero divisor on M/(y ₁, …, y _d−1) M, where (y ₁, …, y _d) is a reducing system of parameters of M (d:= dim_R M).