Positron trapping and annihilation at interfaces between matrix and cylindrical or spherical precipitates modeled by diffusion-reaction theory
Abstract
The exact solution of a diffusionreaction model for the trapping and annihilation of positrons at interfaces of precipitatematrix composites is presented considering both cylindrical or spherical precipitates. Diffusion-limitation is taken into account for interfacial trapping from the surrounding matrix as well as from the interior of the precipitate. Closed-form expressions are obtained for the mean positron lifetime and for the intensity of the positron lifetime component associated with the interface-trapped state. The model contains as special case also positron trapping at extended open-volume defects like spherical voids or hollow cylinders. This makes the model applicable to all types of cylindrical- and spherical-shaped extended defects irrespective of their size and their number density.
Cite
@article{arxiv.1903.09486,
title = {Positron trapping and annihilation at interfaces between matrix and cylindrical or spherical precipitates modeled by diffusion-reaction theory},
author = {Roland Würschum and Laura Resch and Gregor Klinser},
journal= {arXiv preprint arXiv:1903.09486},
year = {2020}
}
Comments
To be published in the Proceedings of International Conference on Positrron Annihilation, 2018; submitted August 16, 2018; Accepted January 8, 2019. AIP Conference Proceedings