Cyclotron cooling to cryogenic temperature in a Penning-Malmberg trap with a large solid angle acceptance

TL;DR

This paper demonstrates that using copper meshes and cryogenic microwave absorbers in a Penning-Malmberg trap effectively cools nonneutral plasma to cryogenic temperatures by reducing cyclotron radiation energy density.

Contribution

It introduces a novel cooling method employing fine copper meshes and cryogenic absorbers to lower plasma temperature via cyclotron radiation control.

Findings

Plasma temperature was significantly reduced.

Effective microwave environment suppression was achieved.

Cryogenic cooling improved plasma confinement.

Abstract

Magnetized nonneutral plasma composed of electrons or positrons couples to the local microwave environment via cyclotron radiation. The equilibrium plasma temperature depends on the microwave energy density near the cyclotron frequency. Fine copper meshes and cryogenic microwave absorbing material were used to lower the effective temperature of the radiation environment in ASACUSA's Cusp trap, resulting in significantly reduced plasma temperature.