Ma, ShuiliangHoward, JohnBlackwell, Boyd D.Thapar, Nandika2015-09-252015-09-250034-6748http://hdl.handle.net/1885/15716Electron density and temperature distributions in the H-1 heliac plasma are measured using the helium line intensity ratio technique based on a collisional-radiative model. An inversion approach with minimum Fisher regularization is developed to reconstruct the ratios of the local emission radiances from detected line-integrated intensities. The electron density and temperature inferred from the He I 667.8/728.1 and He I 728.1/706.5 nm line ratios are in good agreement with those from other diagnostic techniques in the inner region of the plasma. The electron density and temperature values appear to be a little high in the outer region of the plasma. Some possible causes of the discrepancy in the outer region are discussed.http://www.sherpa.ac.uk/romeo/issn/0034-6748..."Publishers version/PDF may be used on author's personal website, institutional website or institutional repository" from SHERPA/RoMEO site (as at 25/09/15). Copyright 2012 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in (Ma, Shuiliang, et al. "Measurements of electron density and temperature in the H-1 heliac plasma by helium line intensity ratios." Review of Scientific Instruments 83.3 (2012): 033102.) and may be found at https://doi.org/10.1063/1.3692756Keywords: Collisional radiative model; Diagnostic techniques; Helium lines; Inner region; Line ratios; Local emissions; Temperature values; Carrier concentration; Electron density measurement; Electrons; Helium; Collisional plasmas2012-03-0710.1063/1.36927562016-02-24