CAREER: Physics of Non-Neutral and Electron-Positron Plasmas Confined in the CNT Stellarator

Columbia University, New York NY

Investigators

Abstract

This CAREER project is focuses on creating and studying confined non-neutral and electron-positron plasmas in the Columbia Non-neutral Torus (CNT), and to use this research program to interact with and educate graduate students, undergraduate students, high school teachers and students, and the general public. CNT is a unique and simple toroidal magnetic confinement device that is specifically designed for the studies proposed here. It will, for the first time, allow a systematic study of plasmas with arbitrary degree of neutrality, from pure electron to quasi-neutral, a systematic study of toroidal magnetic confinement in the presence of extreme electric fields and strong flows, and the creation of the first ever laboratory electron-positron plasma. Electron-positron plasmas are unique in that the mass ratio between the two species is one and the charge ratio is one. Hence, these plasmas are highly symmetric and very different from regular ion-electron plasmas. As a result, electron-positron plasmas have unique properties, such as not supporting acoustic waves and electrostatic drift waves. At the same time, they can be analyzed numerically and analytically more easily than ion-electron plasmas, because both species evolve on the same spatial and temporal scales. Electron-positron plasmas may be considered the hydrogen atom of plasma physics, the simplest possible plasmas. CNT is a state of the art University experiment, with a large degree of involvement of graduate and undergraduate students. It is an ideal training ground for future experimental scientists. It also facilitates interaction and collaboration with high school science teachers and students, a collaboration that will be further expanded in the future.