Anisotropy in broad component of H$\alpha$ line in the magnetospheric device RT-1

TL;DR

This paper reports the detection of temperature anisotropy in the broad component of the Hα line in the RT-1 device, indicating proton temperature anisotropy caused by betatron acceleration, using Doppler spectroscopy.

Contribution

It provides the first evidence of proton temperature anisotropy in a magnetospheric device through spectroscopic measurements.

Findings

Temperature anisotropy observed in Hα line broad component

Proton temperature anisotropy linked to betatron acceleration

Doppler spectroscopy effectively detects anisotropy in plasma

Abstract

Temperature anisotropy in broad component of H$\alpha$ line was found in the ring trap 1 (RT-1) device by Doppler spectroscopy. Since hot hydrogen neutrals emitting a broad component are mainly produced by charge exchange between neutrals and protons, the anisotropy in the broad component is the evidence of proton temperature anisotropy generated by betatron acceleration.