Radial profile measurement of impurity line emissions using space-resolved 3m vacuum ultraviolet spectrometer in LHD

Katai, Ryuji; Morita, S.; Goto, M.

doi:10.1063/1.2221594

Cited by 14 publications

(14 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…VUV spectra have been measured using a spaceresolved VUV system, which consists of a 3 m normal incidence spectrometer with a 1200 grooves/mm grating (65 × 150 mm 2 , 1400 Å blaze with Pt coating), a back-illuminated charged-coupled device (CCD) detector (1024 × 1024 pixels, 13 µm × 13 µm/pixel) and a pair of mirrors for view-angle adjustment [13][14][15]. The size of the CCD exposure area is 13.3 × 13.3 mm 2 .…”

Section: Instrumentationmentioning

confidence: 99%

High-Resolution VUV Spectra of Carbon, Neon and Argon in a Wavelength Range of 250 to 2300 Å for Plasma Diagnostics Observed with a 3 m Normal Incidence Spectrometer in LHD

Katai

Morita

Goto

2007

Plasma and Fusion Research

Self Cite

View full text Add to dashboard Cite

Intrinsic impurities have been much reduced in toroidal fusion devices through the development of several wall-conditioning techniques as well as by the use of carbon materials in the first wall and divertor plates. Impurity elements useful for passive plasma spectroscopy have been then extremely limited. At present, only carbon is a subject for spectroscopic diagnostics in most discharges except for fuel atoms. The use of rare gas as a brighter light source is a method to overcome the present difficulty in passive spectroscopy. Recently, rare gases have also been used for edge cooling to reduce the divertor heat flux. Therefore, high-resolution spectra (∆λ ∼ 0.2 Å) from neon and argon in a 250 to 2300 Å wavelength range have been measured using a 3 m normal incidence spectrometer in Large Helical Device (LHD) and the measured spectra were precisely analyzed. The VUV spectra of carbon, neon and argon are presented for spectroscopic use and their wavelengths are tabulated with their relative intensities. The spectral profiles of almost all the spectral lines measured here are formed by the Doppler broadening and self-absorption processes. The Doppler broadening of neon and argon spectra are plotted against the ionization energies and Doppler spectra from carbon lines are presented. The self-absorption spectra of the hydrogen Lyman-α line, which are found in the LHD high-density discharge, are also presented and the neutral density is analytically estimated.

show abstract

Section: Instrumentationmentioning

confidence: 99%

High-Resolution VUV Spectra of Carbon, Neon and Argon in a Wavelength Range of 250 to 2300 Å for Plasma Diagnostics Observed with a 3 m Normal Incidence Spectrometer in LHD

Katai

Morita

Goto

2007

Plasma and Fusion Research

Self Cite

View full text Add to dashboard Cite

show abstract

“…[2][3][4] The traditional method to determine this parameter is the measurement of ion line Doppler broadening [3][4][5][6] and, more recently, charge exchange spectroscopy. 1 In the fusion devices, the analysis of core temperatures has been performed using x-ray radiation.…”

mentioning

confidence: 99%

Multichannel detector for ion temperature determination in vacuum ultraviolet spectrum

Daltrini

Machida

2007

Review of Scientific Instruments

View full text Add to dashboard Cite

A vacuum ultraviolet spectrometer equipped with a charge coupled device and an open multichannel plate has been used to analyze the temperature of carbon and oxygen ions in the NOVA-UNICAMP tokamak. The detection system was optimized and aligned to minimize the instrumental broadening. Also, higher order diffractions of the emissions were analyzed, resulting in lower experimental errors. The ion temperature was monitored during the tokamak discharge, presenting values between 30 and 70 eV.

show abstract

“…The line emissions from impurity particles in tokamak plasmas are routinely used in many analyses as radiation power loss, transport/rotation phenomena, and ion temperature measurements in different region of plasma [1][2][3]. In addition, many impurity emissions met in divertor or edge regions of large tokamak [4,5] can be comparable to impurity emissions produced by plasmas in smaller tokamaks as TCABR [6].…”

Section: Introductionmentioning

confidence: 99%

VUV spectral line emission measurements in the TCABR tokamak

Machida¹,

Daltrini²,

Severo

et al. 2009

Braz. J. Phys.

View full text Add to dashboard Cite

The study of tokamak plasma light emissions in the vacuum ultraviolet (VUV) region is an important subject since many impurity spectral emissions are present in this region. These spectral emissions can be used to determine the plasma ion temperature and density from different species and spatial positions inside plasma according to their temperatures. We have analyzed VUV spectra from 500Å to 3200Å wavelength in the TCABR tokamak plasma including higher diffraction order emissions. There have been identified 37 first diffraction order emissions, resulting in 28 second diffraction order, 24 third diffraction order, and 7 fourth diffraction order lines. The emissions are from impurity species such as OII, OIII, OIV, OV, OVI, OVII, CII, CIII, CIV, NIII, NIV, and NV. All the spectra beyond 1900Å are from higher diffraction order emissions, and possess much better spectral resolution. Each strong and isolated spectral line, as well as its higher diffraction order emissions suitable for plasma diagnostic is identified and discussed. Finally, an example of ion temperature determination using different diffraction order is presented.

show abstract

Radial profile measurement of impurity line emissions using space-resolved 3m vacuum ultraviolet spectrometer in LHD

Cited by 14 publications

References 9 publications

High-Resolution VUV Spectra of Carbon, Neon and Argon in a Wavelength Range of 250 to 2300 Å for Plasma Diagnostics Observed with a 3 m Normal Incidence Spectrometer in LHD

High-Resolution VUV Spectra of Carbon, Neon and Argon in a Wavelength Range of 250 to 2300 Å for Plasma Diagnostics Observed with a 3 m Normal Incidence Spectrometer in LHD

Multichannel detector for ion temperature determination in vacuum ultraviolet spectrum

VUV spectral line emission measurements in the TCABR tokamak

Contact Info

Product

Resources

About