Spatial sampling of crystal electrons by in-flight annihilation of fast positrons
Article Abstract:
A monoenergetic beam flux of 10(super 5) particles per second has been used to make observations of single- and two-photon annihilation from channelled positrons. It was possible to indicate the ability of channelled positrons to selectively sample valence electrons in a crystal. The enhanced minimum yield seen for two-photon over one-photon annihilation confirmed expectations that two-photon annihilation channelling effects would be extremely sensitive to electron densities in the interstitial areas of crystals.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
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A glimpse of the antiworld
Article Abstract:
The high energy antiprotons traversing through atoms convert some of their energy into electron-positron pairs, but rarely emerge as antihydrogen atoms. An experiment shows that antiprotons in the Low Energy Antiproton Ring passing through a xenon jet form antihydrogen atoms. Antihydrogen atoms, with a speed approximating that of light, escape from the apparatus in tens of nanoseconds. An inaccuracy in working-symmetrical model arises due to the gravitational field and the use of wrong mirrors.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1996
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The production of molecular positronium
Article Abstract:
The production of molecular positronium, a metastable hydrogen-like atom consisting of electron and its antiparticle is described. The formation of the molecule is found to be a very efficient and fast process.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2007
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