- Positron Lifetime Spectroscopy
Positron Lifetime Spectroscopy is a technique in
material scienceused for studying the types and concentrations of atomic sized defects in materials.
positrons are produced through Beta Decay. A typical source would be 22Na, sodium-22.
Positron Behaviour in Materials
positrons will thermalize, slow down, very quickly in a material. This means that they barely penetrate the surface of most materials. After thermalization, the positron will diffuse around the material, interacting with any defects, electromagneticdistortions or potential wells, they encounter. This may result in a change of the positron's state, collapsing its wave functionand reducing the instantaneous chance of electron-positron annihilation. This will change the characteristic lifetime (in some ways similar to mean lifetimeof the positron, which affects the lifetime spectra produced in experiment.
Recently a program named
SimPLhas been produced at the University of Prince Edward Island, PEI, Canada, which attempts to simulatethe positron interaction and model the output spectra.
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