Plasma heating and acceleration in current sheets formed in discharges in argon

N.P Kyrie

doi:10.1051/epjconf/201713203020

Abstract

According to present notion, flares on the sun and other stars, substorms in magnetospheres of Earth and other planets, and disruptive instabilities in tokamak plasma are connected to development of current sheets in magnetized plasma. Therefore, current sheet dynamics and magnetic reconnection processes were studied actively during the last several decades. This paper presents the results of experimental studies of plasma heating and acceleration in current sheets formed in discharges in argon. The temperature and energy of directed motion of argon ions of different degrees of ionization were measured by spectroscopic methods. It was found that Ar II, Ar III and Ar IV ions are localized in different regions of the sheet. It was shown that Ampere forces applied to the sheet can accelerate the argon ions to observed energies.

Highlights

According to present notion, flares on the sun and other stars, substorms in magnetospheres of Earth and other planets, and disruptive instabilities in tokamak plasma are connected to development of current sheets in magnetized plasma
For the current sheets formed in two-dimensional magnetic configurations (p = 28 mTorr, Iz = 45 kA, h = 0.5 kG/cm, Bz = 0), it was found that Ar II, Ar III and Ar IV ions of argon are localized in different regions of the current sheet, depending on their temperature
The Ar II ions are located in relatively cold plasma regions at the periphery with a maximum temperature Ti = (60 ± 15) eV, whereas the Ar III and Ar IV ions are located in hotter central regions of the current sheet with a maximum temperature Ti = (100 – 140) eV

Summary

Introduction

Flares on the sun and other stars, substorms in magnetospheres of Earth and other planets, and disruptive instabilities in tokamak plasma are connected to development of current sheets in magnetized plasma. The paper is concerned with measurements of the temperature and energy of directed motions of ions in laboratory current sheets formed in two-dimensional three-dimensional configurations with a singular X line in argon.

Results

Conclusion