@article{oai:nagoya.repo.nii.ac.jp:00028641,
 author = {Kajita, Shin and Suzuki, Kensuke and Tanaka, Hirohiko and Ohno, Noriyasu},
 issue = {6},
 journal = {Physics of Plasmas},
 month = {Jun},
 note = {Line emissions from helium (He) plasmas have been used for measurement of electron density and temperature in various situations. We performed measurements of He line intensities in recombining plasmas in a divertor simulator, followed by discussion of some potential difficulties of using the line intensity ratio (LIR) method in a divertor environment under detached conditions. When using four line emissions (501.6, 667.8, 706.5, and 728.1 nm), the discrepancy of the results compared to results from the laser Thomson scattering (LTS) method increased along with increasing gas pressure. However, the LIR method agreed well with LTS when a recombination sensitive line emission (447.1 nm) was added. The influence of the transport of metastable atoms is also discussed. Additionally, anomalous characteristics of the LIR method were revealed in hydrogen helium mixture plasmas when the temperature was in the range of 1–4 eV. These anomalies were likely attributable to the dissociative recombination of HeH^+.},
 title = {Helium line emission spectroscopy in recombining detached plasmas},
 volume = {25},
 year = {2018}
}