Journal ArticleDOI
Saturation broadening of laser-induced fluorescence from plasma ions
TLDR
In this paper, the authors test three different prescriptions for plasma experimentalists to avoid saturation broadening while maintaining a strong signal, and identify the prescription that is the easiest to use and the least sensitive to the spatial profile of the laser beam.Abstract:
Saturation broadening is an obstacle in using laser‐induced fluorescence as a plasma diagnostic. The Doppler‐broadened line shape ideally yields the ion velocity distribution function, but at high laser power, saturation of the optical transition leads to additional undesirable line broadening. We test three different prescriptions for plasma experimentalists to avoid saturation broadening while maintaining a strong signal. Based on experiments in an argon plasma, and a semiclassical atomic physics simulation, we have identified the prescription that is the easiest to use and the least sensitive to the spatial profile of the laser beam. This procedure is to measure the laser intensity that leads to saturation on the peak of the spectral line, and then to reduce the intensity to 20% of the saturation level.read more
Citations
More filters
Journal ArticleDOI
Flow, flow shear, and related profiles in helicon plasmas
TL;DR: In this article, the radial profiles of the ion viscosity and ion-neutral momentum transfer rate of a cylindrical argon, helicon, and helium ion plasma were calculated.
Journal ArticleDOI
Measurement of ion motion in a shear Alfvén wave
TL;DR: In this paper, the laser-induced fluorescence (LIF) has been used to measure the E×B0 and polarization drifts of shear Alfven waves in the Large Plasma Device at UCLA.
Journal ArticleDOI
Positive charging of grains in an afterglow plasma is enhanced by ions drifting in an electric field
TL;DR: In this paper, the authors show that the polarity of a dust grain's charge is typically negative, but it can reverse and become positive in an afterglow, when the power sustaining the plasma is switched off.
Journal ArticleDOI
Laser‐induced fluorescence measurement of the dynamics of a pulsed planar sheath
TL;DR: Conrad et al. as mentioned in this paper measured the ion density near the edge of an expanding plasma sheath using laser-induced fluorescence (LIF) using a transition of N+2 [the P12 component of the X 2Σ+g(ν = 0)→B 2ξ+u(ν=0) band] in a N2 plasma.
Journal ArticleDOI
Three-dimensional laser-induced fluorescence measurements in a helicon plasma
TL;DR: In this article, a 3D laser-induced fluorescence (LIF) diagnostic for argon ions in a helicon plasma source is described, with three different laser injection orientations at a single spatial location.
References
More filters
Book
Spectral Line Broadening by Plasmas
Hans R. Griem,W. L. Barr +1 more
TL;DR: SpectSpectral Line Broadening by Plasmas as discussed by the authors provides a theoretical overview of the spectral line broadening mechanism and its application in the field of plasma spectroscopy, with a focus on spectral lines.
Book
Physics of atoms and molecules
B H Bransden,Charles Joachain +1 more
TL;DR: In this paper, the elements of quantum mechanics are defined: electrons, photons and atoms, and the interaction of one-electron atoms with electromagnetic radiation is discussed, and some applications of atomic physics are discussed.
Journal ArticleDOI
Magnetic Multipole Containment of Large Uniform Collisionless Quiescent Plasmas
TL;DR: In this paper, over 1200 Alnico magnets are used to contain a conventional discharge plasma produced by 1-20 A of emission from 6-48 small filaments at − 60 V.
Journal ArticleDOI
Optical Techniques in Plasma Diagnostics
TL;DR: In this paper, a review of optical techniques for plasma diagnostics is presented, focusing on plasma-induced emission and laser-induced fluorescence probes of radical and ionic concentrations and temperatures in low pressure discharges.
Related Papers (5)
Laser‐induced fluorescence measurement of plasma ion temperatures: Corrections for power saturation
Matthew Goeckner,John Goree +1 more