Temperature anisotropy in broad component of Hα 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.
@article{arxiv.1602.01165,
title = {Anisotropy in broad component of H$\alpha$ line in the magnetospheric device RT-1},
author = {Yohei Kawazura and Noriki Takahashi and Zensho Yoshida and Masaki Nishiura and Tomoaki Nogami and Ankur Kashyap and Yoshihisa Yano and Haruhiko Saitoh and Miyuri Yamasaki and Toshiki Mushiake and Masataka Nakatsuka},
journal= {arXiv preprint arXiv:1602.01165},
year = {2016}
}