Positron extraction to an electromagnetic field free region

TL;DR

This paper presents a high-efficiency method for extracting and focusing positron bunches into a field-free region, with potential advantages for various applications, validated by simulations.

Contribution

It introduces a novel scheme achieving about 90% positron extraction efficiency into a field-free region with precise bunching and focusing.

Findings

Achieved ~90% positron extraction efficiency.

Bunched positrons to approximately 1 ns (FWHM).

Focused positron beam to less than 1 mm ({}).

Abstract

We describe a scheme for high efficiency (about 90%) extraction of 50 ns positron bunches from a buffer gas trap in an electromagnetic field free region. The positrons are time bunched to approximately 1 ns (FWHM) and focussed to less than 1 mm ({\sigma}). The target is kept at ground potential which is an advantage for many applications. The results compare well with SIMION simulations.