@article{af4f3825c71e4e86b3f6eb5f5c97745d,
title = "Spectroscopic measurement of hydrogen atom density in a plasma produced with 28 GHz ECH in QUEST",
abstract = "The spatial distribution of the hydrogen atom density was evaluated in a spherical tokamak (ST) plasma sustained only with 28 GHz electron cyclotron heating (ECH). The radially resolved Hδ emissivity was measured using multiple viewing chord spectroscopy and Abel inversion. A collisional-radiative (CR) model analysis of the emissivity resulted in a ground-state hydrogen atom density of 1015-1016 m-3 and an ionization degree of 1-0.85 in the plasma.",
author = "Satoru Mori and Taiichi Shikama and Kazuaki Hanada and Nao Yoneda and Arseniy Kuzmin and Masahiro Hasuo and Hiroshi Idei and Takumi Onchi and Akira Ejiri and Yuki Osawa and Yi Peng and Kyohei Matsuzaki and Shinichiro Kado and Keiji Sawada and Takeshi Ido and Kazuo Nakamura and Ryuya Ikezoe and Yoshihiko Nagashima and Makoto Hasegawa and Kengo Kuroda and Aki Higashijima and Takahiro Nagata and Shun Shimabukuro",
note = "Funding Information: This research was funded by JSPS KAKENHI (18K03576), bilateral (NIFS16KUTR114, NIFS19KUTR140), and LHD project research (NIFS16KOAP031) collaboration programs of the National Institute for Fusion Science, and the collaborative research program of the Research Institute for Applied Mechanics, Kyushu University (30FP-38). Publisher Copyright: {\textcopyright} 2020 by the authors.",
year = "2020",
month = sep,
doi = "10.3390/ATOMS8030044",
language = "English",
volume = "8",
journal = "Atoms",
issn = "2218-2004",
publisher = "Multidisciplinary Digital Publishing Institute (MDPI)",
number = "3",
}