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Materials Characterization with Intense Positron Beams

Published online by Cambridge University Press:  22 February 2011

I. J. Rosenberg
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
R. H. Howell
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
M. J. Fluss
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
P. Meyer
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
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Abstract

We have developed an apparatus that provides a high flux, low energy, monoenergetic positron beam to investigate various processes which occur when a positron beam impinges on a metal surface, including annihilation at the surface, trapping in vacancies, and the emission of both fast and thermally desorbed positronium. We report here the first angular correlation of annihilation gamma-rays measurements and positronium time of flight experiments at a material surface. We applied a simple free electron model which explains the general trend of the data but differences due to the surface specific properties and the deviation from a free electron metal are evident.

Type
Research Article
Copyright
Copyright © Materials Research Society 1985

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References

REFERENCES

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