Download or read book Electron Capture from Solids by Positrons written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The capture of electrons in solids is modified from that in gasses by several factors. The most important is the collective interaction of the electrons which results in a density of electron states in the solid in wide bands. Also the high density of electrons in many solids gives a high frequency of interaction as compared to gasses, and quickly destroys any electron-positron states in the metal matrix. Consequently, most positrons implanted in a metal will rapidly thermalize, and unless they reach the surface will annihilate with an electron in an uncorrelated state. Positronium formation from positrons scattered at a metal surface is analogous to ion neutralization however, most of the positronium comes from positrons passing through the surface from the bulk. The dominant motivation for studying positronium formation has been the hope that the distribution of the electrons at the surface would be obtained through the annihilation properties of positrons trapped at the surface or through analysis of the energy and angular distributions of the positronium emitted into the vacuum. These distributions have been measured and are included in this paper. 17 refs.
Download or read book Positrons in Solids written by Pekka Hautojärvi and published by Springer. This book was released on 1979 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Interaction of Charged Particles with Solids and Surfaces written by Alberto Gras-Martí and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 699 pages. Available in PDF, EPUB and Kindle. Book excerpt: Early in 1989, while most of us were gathered in the Mediterranean five-centuries-old city of Alacant, the idea of a school on stopping and particle penetration phenomena came to our minds. Later that year when discussing this plan with some of the participants in the 13th International Conference on Atomic Collisions in Solids in Aarhus, we were pleased to note that the proposal was warmly welcomed indeed by the community. An Advanced Study Institute on this or a related subject had not been organized in the last decade. Because of the progress made particularly in the interaction of high energy beams with matter, and the many applications which the general subject of the stopping of charged particles (ions and electrons) in matter enjoys, a Study Institute appeared a worthy enterprise. Even though several international conference series cover developments in these areas, they miss tutorial introductions to the field. The title chosen was Interaction of Charged Particles with Solids and Surfaces, and the objectives were stated as follows: "to cover theory and experiments, including selected applications and hot topics, of the stopping of charged particles (ions and electrons) in matter. The emphasis will be on outlining the areas where further effort is needed, and on specifying the basic needs in applications. Fundamental concepts will prevail over applications, and the character of the Institute as a school will be stressed. " The school was directed by Fernando Flores (Spain), Herbert M. Urbassek (Germany), Nestor R.
Download or read book Atomic Physics with Positrons written by J.W. Humberston and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NATO Advanced Research Workshop on Atomic Physics with Positrons, which was held at University College London during 15-18 July 1987, was the fourth meeting in a series devoted to the general theme of positron colli sions in gases. Previous meetings have been held at York University, Toronto (1981); Royal Holloway College, Egham (1983) and Wayne State Uni versity, Detroit (1985). Recent very significant improvements in positron beam currents, due to the development of more efficient moderators and the use of more intense positron sources, are making possible an increasingly sophisticated range of experiments in atomic collision physics. Whereas a few years ago only total scattering cross sections could be determined, measurements can now be made of various partial and differential cross sections. Intense positron beams are also being used to produce positronium beams and already, as reported here, preliminary investigations have been made of collisions of positronium with several target systems. These experimental developments have stimulated, and been stimulated by, steady, if somewhat less spectacu1ar,progress in associated theoretical studies. Both aspects of the field are well represented in these Proceed ings.
Download or read book Electron Capture to Positron Emission Ratios for 140Pr 141Nd and 143Sm written by Jerry Lynn Evans and published by . This book was released on 1972 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Positron Studies of Solids Surfaces and Atoms written by Allen P. Mills and published by . This book was released on 1986 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annihilation of Positrons in Solids written by Ing-Jiunn Ma and published by . This book was released on 1960* with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Positron Spectroscopy of Solids written by Società italiana di fisica and published by IOS Press. This book was released on 1995 with total page 807 pages. Available in PDF, EPUB and Kindle. Book excerpt: The lifetime of a positron inside a solid is normally less than a fraction of nanosecond. This is a very short time on a human scale, but is long enough to enable the positron to visit an extended region of the material, and to sense the atomic and electronic structure of the environment. Thus, we can inject a positron in a sample to draw from it some signal giving us information on the microscopic properties of the material. This idea has been successfully developed in a number of positron-based techniques of physical analysis, with resolution in energy, momentum, or position. The complex of these techniques is what we call now positron spectroscopy of solids. The field of application of the positron spectroscopy extends from advanced problems of solid-state physics to industrial applications in the area of characterization of high-tech materials. This volume focuses the attention on the physics that can be learned from positron-based methods, but also frames those methods in a wider context including other experimental approaches. It can be considered as a textbook on positron spectroscopy of solids, the sort of book that the newcomer takes for his approach to this field, but also as a useful research tool for the expert.
Download or read book Positrons in Solids written by P. Hautojärvi and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: In condensed matter initially fast positrons annihilate after having reached equi librium with the surroundings. The interaction of positrons with matter is governed by the laws of ordinary quantum mechanics. Field theory and antiparticle properties enter only in the annihilation process leading to the emergence of energetic photons. The monitoring of annihilation radiation by nuclear spectroscopic methods provides valuable information on the electron-positron system which can directly be related to the electronic structure of the medium. Since the positron is a positive electron its behavior in matter is especially interesting to solid-state and atomic physi cists. The small mass quarantees that the positron is really a quantum mechanical particle and completely different from any other particles and atoms. Positron physics started about 25 years ago but discoveries of new features in its interac tion with matter have maintained continuous interest and increasing activity in the field. Nowadays it is becoming part of the "stock-in-trade" of experimental physics.
Download or read book Positron and Electron Emission from Solid Surfaces written by Nicola Overton and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Positron Electron Gas Scattering Proceedings Of The 3rd International Workshop written by Walter E Kauppila and published by World Scientific. This book was released on 1986-04-01 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: This workshop discusses the current state and future directions of research in positron — gas scattering, particularly in the relationship between positron and electron scattering by the same atoms and molecules. The possible applications of positron — gas scattering to astrophysical phenomena have also been discussed.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetics and Thermodynamics of Fast Particles in Solids written by Yurii Kashlev and published by CRC Press. This book was released on 2012-10-11 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: Kinetics and Thermodynamics of Fast Particles in Solids examines the kinetics and non-equilibrium statistical thermodynamics of fast charged particles moving in crystals in different modes. It follows a line of research very different from traditional ways of constructing a theory of radiation effects, which gives a purely mechanistic interpretation of particle motion. In contrast, this book takes into account the thermodynamic forces due to separation of the thermodynamic parameters of the subsystem of particles ("hot" atoms) on the parameters of the thermostat (electrons and lattice), in addition to covering the various mechanisms of collisions. Topics Include: Construction of a local kinetic equation of Boltzmann type for fast particles interacting with the conduction electrons and lattice vibrations, on the basis of the principles of Bogolyubov’s kinetic theory Calculation of the equilibrium energy and angular distributions of fast particles at a depth of the order of coherence length, and the evolution of particle distribution with increasing depth of penetration of the beam Calculation of transverse quasi-temperature of channeled particles with the heating of the beam in the process of diffusion of particles in the space of transverse energies, as well as cooling the beam through a dissipative process Research in the framework of non-equilibrium thermodynamics of the relaxation kinetics of random particles, including the thermodynamics of positronium atoms moving in insulators under laser irradiation Analysis of the kinetics of hot carriers in semiconductors and thermalization of hot carriers, as well as the calculation of the statistical distribution of ejected atoms formed during the displacement cascade The book sets a new direction of the theory of radiation effects in solids—non-equilibrium statistical thermodynamics of fast particles—and aims to focus and aid the reader in the study of new areas of investigation in this area.
Download or read book Electron Capture by Tetra and Di chlorobenzene Molecules written by Niels Jørgen Pedersen and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Ratio of Electron Capture to Positron Emission in Heavy Nuclei written by William Bruce McFarland and published by . This book was released on 1977 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of Electrons and Positrons in Imperfect Solids written by Risto Nieminen and published by . This book was released on 1975 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemistry 2e written by Paul Flowers and published by . This book was released on 2019-02-14 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemistry 2e is designed to meet the scope and sequence requirements of the two-semester general chemistry course. The textbook provides an important opportunity for students to learn the core concepts of chemistry and understand how those concepts apply to their lives and the world around them. The book also includes a number of innovative features, including interactive exercises and real-world applications, designed to enhance student learning. The second edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Substantial improvements have been made in the figures, illustrations, and example exercises that support the text narrative. Changes made in Chemistry 2e are described in the preface to help instructors transition to the second edition.
