Keywords: annihilation rate, positron annihilation spectroscopy, PAS, probability, energy transfer modelling, polyethylene terephthalate, PET films, film thickness, aluminium foils, water, nuclear filters
Positron annihilation rates in materials
The study of positron annihilation rate is one subject of a relatively new method of material structure analysis ? positron annihilation spectroscopy. Polyethylene Terephthalate (PET) films have been studied by positron annihilation rate measurement. The correlation between annihilation rates and the PET film thickness was established. Similar studies were carried out for aluminium foils and water. The results give information on the probability of positron annihilation per unit of time and per unit of material thickness that is described by an explicit function of the energy transfer model.