A quantum kinetic equation coupled with Maxwell's equation is used to estimate the laser power required at an x-ray free-electron laser (XFEL) facility to expose intrinsically quantum effects in the process of QED vacuum decay via spontaneous pair production. A 9 -TW-peak XFEL laser with photon energy of 8.3 keV could be sufficient to initiate particle accumulation and the consequent formation ...

The "parent" tertiary alkyl chloroformate, tert-butyl chloroformate, is unstable, but the tert-butyl chlorothioformate (1) is of increased stability and a kinetic investigation of the solvolyses is presented. Analyses in terms of the simple and extended Grunwald-Winstein equations are carried out. The original one-term equation satisfactorily correlates the data with a sensitivity towards chang...

Flow over a downstream-facing step is predicted using the F.E.M. A two-equation model of turbulence is employed where the transport of turbulence kinetic energy and dissipation rate are depicted using transport-type equations, i.e. the two-equation model of turbulence. The results obtained are compared with other models and experimental results. Generally, the model was found to be under-predic...

A linearization is developed for Mieussens’s discrete velocity model (see, e.g., [L. Mieussens, Discrete-velocity models and numerical schemes for the Boltzmann-BGK equation in plane and axisymmetric geometries, J. Comput. Phys. 162 (2000) 429–466]) for kinetic equations. The basic idea is to use a linearized expression of the reference distribution function in the kinetic equation, instead of ...

Abstract. We develop an analytical tool which is adept for detecting shapes of oscillatory functions, is useful in decomposing homogenization problems into limit-problems for kinetic equations, and provides an efficient framework for the validation of multi-scale asymptotic expansions. We apply it first to a hyperbolic homogenization problem and transform it to a hyperbolic limit problem for a ...

Abstract. The paper discusses the solution of a simple kinetic equation of the type used for the computation of the change of the chemical composition in stars like the Sun. Starting from the standard form of the kinetic equation it is generalized to a fractional kinetic equation and its solutions in terms of H-functions are obtained. The role of thermonuclear functions, which are also represen...

We develop an analytical tool which is adept for detecting shapes of oscillatory functions, is useful in decomposing homogenization problems into limit-problems for kinetic equations. and provides an efficient framework for the validation of multi-scale asymptotic expansions. We apply it first to a hyperbolic homogenization problem and transform it to a hyperbolic limit problem for a kinetic eq...

This Brief Communication is about the study of diatomic gas shock structure based on the nonequilibrium gas-kinetic Bhatnagar–Gross–Krook (BGK) model, where an additional rotational energy relaxation equation is added. The BGK Navier–Stokes flow solver is extended to solve the nonequilibrium gas kinetic model. The numerical solutions are compared with the experiment measurements and direct simu...

Mathematical models used to predict the behavior of genetically modified organisms require 1). a (rather) large number of state variables, and 2). complicated kinetic expressions containing a large number of parameters. Since these models are hardly identifiable and of limited use in model-based optimization and control strategies, a generic methodology based on sensitivity function analysis is...

We develop the formalism discussed previously in hep-ph/0601209 and hep-ph/0605246 to construct a kinetic theory that provides insight into the earliest “Glasma” stage of a high energy heavy ion collision. Particles produced from the decay of classical fields in the Glasma obey a Boltzmann equation whose novel features include an inhomogeneous source term and new contributions to the collision ...