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Production or annihilation of positrons with bound electrons
Physical Review A, 1996We have investigated the recently reported discrepancy between theory and a new experiment [Palathingal et al., Phys. Rev. A 51, 2122 (1995)] for single-quantum annihilation of positrons with bound electrons. Fully relativistic calculations of total cross sections for the production and the annihilation of positrons involving an electron bound in the K
, Bergstrom, , Kissel, , Pratt
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Charm Threshold in Electron-Positron Annihilation
Physical Review Letters, 1976Available data on new mesons discovered at SPEAR are sufficient to determine the spectrum of low-lying charmed mesons and to provide a complete description of the threshold structure of $R$ in the framework of the charmonium model. A number of simple tests are proposed to confirm the charm interpretation.
Kenneth Lane, E. Eichten
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Positron-annihilation studies of the electronic structure of NiO
Physical Review B, 1989We report the first two-dimensional angular correlation of positron-annihilation radiation (ACPAR) studies of the positron-electron momentum distribution for NiO. The data contain two components: a large, isotropic, corelike electron contribution and a remaining valence-electron contribution. We access the covalency structure by modeling the anisotropy
, Wachs +8 more
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Semiexclusive production in electron-positron annihilation
Physical Review D, 1994We present a thorough analysis of the direct semiexclusive production in quantum chromodynamics (QCD) of single, highly isolated mesons from electron-positron or two-photon initial states. Corrections of higher order and of subleading twist are considered, and potential divergences in the naive calculation are contained. Monte Carlo methods are used to
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Annihilation of Positrons with Atomic Electrons
2016We analyze various channels for the annihilation of positrons with atomic electrons. Since in the annihilation process a large energy exceeding 1 MeV is released, relativistic analysis is required even in the case of slow positrons. We study in detail the dominative two-photon annihilation process on the Bethe ridge and outside it.
Evgeny G. Drukarev +1 more
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Deep electroproduction and deep electron-positron annihilation
Annals of Physics, 1973Abstract The problem of continuation of the scaling functions for deep inelastic electron scattering into deep inelastic annihilation is discussed. Dynamical models are produced for which analytic continuation connects the two scaling functions and the general conditions are discussed.
RAUL GATTO +2 more
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Electron-Positron Annihilation
2019Abstract This chapter works out the theory of electron-positron annihilation to muon pairs as a model for electron-positron annihilation to quarks. It explains that this naive model provides a good description of observed properties of the process of electron-positron annihilation to hadrons.
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Three-Photon Annihilation of an Electron-Positron Pair
Physical Review, 1949Annihilation of an electron-positron pair accompanied by the emission of three photons is discussed for the case of small relative velocity of the two particles. The energy spectrum of the photons is derived and the cross section for the process is calculated.
Ore, A., Powell, J. L.
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Duality and electron-positron annihilation at high energy
Il Nuovo Cimento A, 1973General constraints of duality are applied to annihilation processes e−e+→h + anything, where h stands for meson or baryon octets. We consider all planar dual terms, as well as a possible background contribution. The interrelation of duality and dominance of specific terms is investigated.
M. Chaichian, H. Satz, S. Kitakado
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Collective electron-positron annihilation
Physics Letters A, 1990Abstract The phenomenon of collective spontaneous annihilation of a magnetized electron-positron plasma is predicted. Like superradiance in systems with discrete energy spectra, collective annihilation leads to the generation of powerful coherent radiation with the rate of this process considerably exceeding the spontaneous annihilation and ...
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