Some most representative results for semicrystalline polymers by positron annihilation spectroscopy method, showing the influence of crystallinity and morphology of samples on positron annihilation characteristics, are reminded. The latest finding of the author’s experiment on modified polyamide 6 is presented. The latter reveals that the interfacial zone between a lamella and an amorphous regi...

A general method for calculating next-to-leading order cross sections in perturbative QCD is presented. The algorithm is worked out for calculating N -jet cross sections in hadron-hadron collisions. The generalization of the scheme to performing caclulations for other QCD process, such as electron-positron annihilation or in deep inelastic scattering is also straightforward. As an illustration ...

I present an introduction to the NRQCD factorization method for calculating annihilation rates and inclusive production rates for heavy quarkonium. Using this method, annihilation decay rates and sufficiently inclusive cross sections are factored into long-distance NRQCD matrix elements and perturbative short-distance coefficients. I derive the velocity-scaling rules that are used to estimate t...

The neutralino, the lightest stable supersymmetric particle, is a strong theoretical candidate for the missing astronomical ”dark matter”. Depending on their annihilation cross section, relic neutralinos from early formation of the Universe trapped in orbits around massive objects may currently be annihilating at measurable rates. The Minimal Supersymmetric extension of the Standard Model predi...

We study precise calculation of neutralino relic density in the minimal supergravity model. We compare the exact formula for the thermal average of the neutralino annihilation cross section times relative velocity with the expansion formula in terms of the temperature, including all the contributions to neutralino annihilation cross section analytically. We confirm that the expansion formula fa...

We assume that nucleon antinucleon annihilation is a fast process leading to a classical coherent pion pulse. We develop the quantum description of such pion waves based on the method of coherent states. We study the consequences of such a description for averages of charge types and moments of distributions of pion momenta with iso-spin and four-momentum conservation taken into account. We bri...

We suggest a method of singular terms regularization in potential model of N N interaction. This method is free from any uncertainties, related to the usual cutoff procedure and based on the fact, that in the presence of sufficiently strong short-range annihilation N and ¯ N never approach close enough to each other. The effect of mentioned singular terms of OBE potential, modified by annihilat...

Positron annihilation spectroscopy is often used to analyze the local electronic structure of materials of technological interest. Reliable theoretical tools are crucial to interpret the measured spectra. Here, we propose a parameter-free gradient correction scheme for a local-density approximation obtained from high-quality quantum Monte Carlo data. The results of our calculations compare favo...

In this article we unveil a new structure in the space of operators of the XXZ chain. For each α we consider the space Wα of all quasi-local operators, which are products of the disorder field qα P 0 j=−∞ σ 3 j with arbitrary local operators. In analogy with CFT the disorder operator itself is considered as primary field. In our previous paper, we have introduced the annhilation operators b(ζ),...