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Related papers: Positronium lifetime in polymers

200 papers

In this work, relationships between the free volume and various fundamental physical properties (density, surface tension and transport properties) of ionic liquids were investigated. Two imidazolium ionic liquids…

Chemical Physics · Physics 2014-04-02 Yang Yu , Dana Bejan , Reinhard Krause-Rehberg

Various Hamiltonian models have been derived for chemical structures belonging to living organisms while the Hamiltonian concept was not applied to life as a whole. However, Hamiltonian components were recently defined for living organisms…

General Physics · Physics 2007-05-23 Michel Bounias

This talk gives an elementary introduction to the basic properties of positronium. Recent progress in theoretical studies of the hyperfine splitting and lifetime of the ground state is reviewed. Sensitivity of these precisely measured…

High Energy Physics - Phenomenology · Physics 2011-04-15 Andrzej Czarnecki

Recent experimental data are analyzed, concerning the half-lives of the 229mTh isomer in neutral atoms and various ions. Calculation is performed on the united platform of interplay of traditional and subthreshold resonance conversion.…

Nuclear Theory · Physics 2018-10-05 F. F. Karpeshin , M. B. Trzhaskovskaya

Purpose: Measuring the ortho-positronium (oPs) lifetime in human tissue bears the potential of adding clinically relevant information about the tissue microenvironment to conventional positron emission tomography (PET). Through phantom…

Positronium annihilation amplitudes that are computed by assuming a factorization approximation with on-shell intermediate leptons do not exhibit good analytical behaviour. Using dispersion techniques, we find new contributions that…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Lopez Castro , J. Pestieau , C. Smith , S. Trine

We present a calculation of the branching ratio of orthopositronium decay into an invisible mode, which is done in the context of Mirror World models, where ordinary positronium can disappear from our world due to oscillation into its…

High Energy Physics - Phenomenology · Physics 2013-05-30 S. V. Demidov , D. S. Gorbunov , A. A. Tokareva

Lattice thermal conductivities of zincblende- and wurtzite-type compounds with 33 combinations of elements are calculated with the single-mode relaxation-time approximation and linearized phonon Boltzmann equation from first-principles…

Materials Science · Physics 2015-06-30 Atsushi Togo , Laurent Chaput , Isao Tanaka

Whether in the Standard Model or beyond it, neutrinos contribute to the invisible decay mode of orthopositronium but practically not at all to that of parapositronium. Although this remark does not resolve the orthopositronium decay puzzle,…

High Energy Physics - Phenomenology · Physics 2009-10-28 Jan Govaerts , Marc Van Caillie

The results of positron annihilation lifetime spectroscopy measurements on undoped, electron irradiated, and Nb doped SrTiO3 single crystals are reported. Perfect lattice and vacancy defect positron lifetimes were calculated using two…

Materials Science · Physics 2009-06-30 R. A. Mackie , S. Singh , J. Laverock , S. B. Dugdale , D. J. Keeble

One of the features of the triplet state of positronium (ortho-Positronium)atoms is its relatively longer lifetime when compared to the singlet states ofpositronium (para-Positronium) atoms. The most probable decay of ortho-Positronium is…

Instrumentation and Detectors · Physics 2020-02-19 Juhi Raj , Kamil Dilski , Eryk Czerwinski

Classical motion of positronium embedded in a magnetic field is studied, and computation shows the emergence of chaotic orbits. Recent work investigating quantum behavior of this system predicts extremely long lifetimes. Chaos assisted…

Plasma Physics · Physics 2007-05-23 J. L. Anderson , R. K. Murawski , G. Schmidt

We calculate the lifetime of both the o-Ps and the p-Ps positronium annihilation decay $ Ps\to\gamma\gamma$ in the strong circular polarized laser field. We take a strategy of the factorization to separate the effects caused by the Coulomb…

High Energy Physics - Phenomenology · Physics 2015-06-16 Yu-Qi Chen , Pei Wu

The results of ab initio calculation of E1 amplitudes, lifetimes,and polarizabilities for several low-lying levels of ytterbium are reported. The effective Hamiltonian for the valence electrons has been constructed in the frame of CI+MBPT…

Atomic Physics · Physics 2009-10-31 S. G. Porsev , Yu. G. Rakhlina , M. G. Kozlov

A living polymers transition is found in molecular dynamics simulations of a charge-symmetric size-asymmetric electrolyte with no anisotropic interactions. The fluid has strong polymeric character at low temperatures, where it consists of…

Statistical Mechanics · Physics 2007-05-23 Sorin Bastea

Nonradiative exciton lifetime in silicon is determined by comparison of the experimental and theoretical curves of bulk minority charge carriers lifetime on doping and excitation levels. This value is used to analyze the influence of…

Materials Science · Physics 2016-12-21 A. V. Sachenko , V. P. Kostylyov , V. M. Vlasyuk , I. O. Sokolovskyi , M. Evstigneev

Positron scattering and annihilation on noble gas atoms below the positronium formation threshold is studied ab initio using many-body theory methods. The many-body theory provides a near-complete understanding of the…

Atomic Physics · Physics 2014-09-12 D. G. Green , J. A. Ludlow , G. F. Gribakin

A many-body theory approach is developed for the problem of positron-atom scattering and annihilation. Strong electron-positron correlations are included non-perturbatively through the calculation of the electron-positron vertex function.…

Atomic Physics · Physics 2007-05-23 G. F. Gribakin , J. Ludlow

We calculate the inelastic lifetime of an electron quasiparticle due to Coulomb interactions in an electron liquid at low (or zero) temperature in two and three spatial dimensions. The contribution of "exchange" processes is calculated…

Strongly Correlated Electrons · Physics 2009-11-10 Zhixin Qian , Giovanni Vignale

Measurements of lifetimes can be done in two ways. For very short lived particles, the width can be measured. For long lived ones, the lifetime can be directly measured, for example, using a displaced vertex. Practically, the lifetime…

High Energy Physics - Phenomenology · Physics 2009-01-06 Yuval Grossman , Itay Nachshon