Simulation of Positronium: Toward More Realistic Models of Void Spaces in Materials

摘要

An exact treatment of the positron and electron in a two-chain, Path Integral Monte Carlo (PIMC) simulation is used to calculate both self-annihilation and pickoff rates at finite temperature. It has already been demonstrated that this technique can reproduce and extend results of simple theories of positrons and positronium (Ps) in spherical voids. Here, we include the effect of the linear dielectric response of a homogeneous material on the annihilation rate of positrons and Ps. In addition, we find lifetimes and structural information for Ps in cylindrical channels, both with and without adsorbed fluid atoms.