Positron spectroscopy

When a positron meets an electron, they form a short-lived species called positron-ium before they annihilate and emit two gamma rays with characteristic energies in opposite directions. Most important for its application in materials analysis is the fact that the positron first roams around the solid sample before settling down with an electron, because it usually will end up at a defect, meaning that positron annihilation 

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A. Dupasquier and A.P. Mills Jr. (Eds.), Positron Spectroscopy of Solids. Proceedings of the International School of Physics Enrico Fermi, Course CXXV, Varenna 6-16 July, 1993, IOS Press, Amsterdam, 1995. 

Like Mossbauer spectroscopy, positron spectroscopy is a nuclear process for probing the chemical and physical environments of solid materials. It is a more versatile technique than Mossbauer spectroscopy, but it does not provide as much information on the structure surrounding the nucleus or the immediate environment of the atom. 

POSITRON SPECTROSCOPY OF LIQUID CRYSTALLINE ORGANIC MATERIALS CONTAINING C60 FULLERENES... 

A broad overview of traditional methods and recent developments in experimental positron spectroscopy is presented. A discussion of the generation and detection of positrons and their annihilation radiation is followed by a survey of techniques used for positron lifetime measurement, Doppler broadening spectroscopy and angular correlation of annihilation radiation, and the opportunities presented by combining these methods (e.g. in age-momentum correlation) and/or extending their capabilities by the use of monoenergetic positron beams. Novel spectroscopic and microscopic techniques using positron beams are also described. 

Xie, L Gidley, D.W., Hristov, H.A., Yee, A.F. (1995) Evolution of nanometer voids in polycarbonate under mechanical stress and thermal expansion using positron spectroscopy . J. Poly. Sci Part B Poly. Phys. 33, 77. 

J. Kanzow, F. Faupel, W. Egger, P. Sperr, G. Kogel, C. Wehlack, W. Possart, Depth-resolved analysis of the ageing behaviour of epoxy resin thin films by positron spectroscopy, Proc. oral pres., 7th European Adhesion Conference EURADH 2004, Ereiburg im Breisgau, September 5-9, 2004. 

Depth-Resolved Analysis of the Aging Behavior of Epoxy Thin Films by Positron Spectroscopy... 

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