THERMAL EXCITATION ENERGY OF TRAPPED  ELECTRONS AT LOW TEMPERATURE STUDIED  THROUGH POSITRON ANNIHILATION LIFETIME  SPECTROSCOPY

Farzana  Nahid; Md. Rashedur  Rahman

doi:10.53808/KUS.2013.11and12.1104-E

Authors

Farzana Nahid Physics Discipline, Khulna University, Khulna 9208, Bangladesh
Md. Rashedur Rahman Physics Discipline, Khulna University, Khulna 9208, Bangladesh

DOI:

https://doi.org/10.53808/KUS.2013.11and12.1104-E

Keywords:

Positronium formation, trapped electron, high density polyethylene, low temperature, ortho-positronium

Abstract

Positronium (Ps) formation has been studied in high density polyethylene (HDPE) below and around gamma transition temperature (Tγ). The increase in ortho-positronium (o-Ps) intensity (I3) with time due to trapped electrons at different rate has been discussed in terms of different possible models. Some calculation have been performed to find the thermal activation energy of trapped electrons.

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