scholarly journals Measurement of Electron Density from Stark-Broadened Nanomaterial Plasma

2018 ◽  
Author(s):  
Ashraf M. EL Sherbini ◽  
Ahmed E. EL Sherbini ◽  
Christian G. Parigger
Keyword(s):  
Electron Density ◽  
Optical Emission Spectroscopy ◽  
Optical Breakdown ◽  
Optical Emission ◽  
Photon Absorption ◽  
Line Profiles ◽  
Balmer Series ◽  
Line Asymmetry ◽  
Atomic Lines

This work communicates results from optical emission spectroscopy following laser-induced optical breakdown at or near nanomaterial. Selected atomic lines of silver are evaluated for consistent determination of electron density. Comparisons are presented with Balmer series hydrogen results. Of particular interest are measurements free of self-absorption effects. For several silver lines, asymmetries are observed in the recorded line profiles. Electron densities of interest range from 0.5 to 3 × 1017 cm-3, for 5 nanosecond Q-switched Nd:YAG radiation at wavelengths of 1064, 532, and 355 nm, and for selected silver emission lines including 328.0, 338.2, 768.7, and 827.3 nm, and the hydrogen alpha Balmer series line at 656.3 nm. Line asymmetries are presented for the 328.0 nm Ag I line that is measured following generation of the plasma due to multiple photon absorption. This work explores electron density variations for different irradiance levels, and reports spectral line asymmetry of resonance lines for different laser fluence levels.

scholarly journals Measurement of Electron Density from Stark-Broadened Spectral Lines Appearing in Silver Nanomaterial Plasma

Atoms ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 44 ◽  
Author(s):  
Ashraf EL Sherbini ◽  
Ahmed EL Sherbini ◽  
Christian Parigger
Keyword(s):  
Electron Density ◽  
Optical Breakdown ◽  
Optical Emission ◽  
Spectral Lines ◽  
Photon Absorption ◽  
Balmer Series ◽  
Line Asymmetry ◽  
Atomic Lines ◽  
532 Nm

This work communicates results from optical emission spectroscopy following laser-induced optical breakdown at or near nanomaterial. Selected atomic lines of silver are evaluated for a consistent determination of electron density. Comparisons are presented with Balmer series hydrogen results. Measurements free of self-absorption effects are of particular interest. For several silver lines, asymmetries are observed in the recorded line profiles. Electron densities of interest range from 0.5 to 3 × 1017 cm−3 for five nanosecond Q-switched Nd:YAG radiation at wavelengths of 1064 nm, 532 nm, and 355 nm and for selected silver emission lines including 328.06 nm, 338.28 nm, 768.7 nm, and 827.3 nm and the hydrogen alpha Balmer series line at 656.3 nm. Line asymmetries are presented for the 328.06-nm and 338.28-nm Ag I lines that are measured following generation of the plasma due to multiple photon absorption. This work explores electron density variations for different irradiance levels and reports spectral line asymmetry of resonance lines for different laser fluence levels.

scholarly journals The Expected behaviour of the Hydrogen Lyman Lines in Solar Flares

1972 ◽  
Vol 14 ◽  
pp. 824-824
Author(s):  
Z. Švestka ◽  
L.D. De Feiter
Keyword(s):  
Electron Density ◽  
Solar Flares ◽  
Line Profiles ◽  
Stark Broadening ◽  
Hydrogen Atoms ◽  
Measured Intensity ◽  
Balmer Series ◽  
Model Calculations ◽  
Intensity Measurements

While the merging of the higher lines of the Balmer series emitted by solar flares is solely determined by the electron density, the merging of the high Lyman lines is determined both by the electron density, through Stark broadening of the line absorption coefficient, and by the total number of hydrogen atoms in the flare, through the effect of self-absorption. Preliminary results of model calculations indicate that two or more intensity measurements, each midway between two consecutive lines of the Lyman series (lines 3–4, 4–5, 5–6) allow the determination of the column density of hydrogen atoms in the ground state provided that the electron density is known. One can believe that in between the Lyman lines only the flare elements contribute to the measured intensity since excited interflare matter of much lower electron density produces line profiles of substantially smaller width. Thus the data in between the lines can be reasonably compared to the Ne values deduced from high members of the Balmer series.

scholarly journals Laboratory Hydrogen-Beta Emission Spectroscopy for Analysis of Astrophysical White Dwarf Spectra

2018 ◽  
Author(s):  
Christian G Parigger ◽  
Kyle A. Drake ◽  
Christopher M Helstern ◽  
Ghaneshwar Gautam
Keyword(s):  
Electron Density ◽  
White Dwarf ◽  
Emission Spectroscopy ◽  
Hydrogen Plasma ◽  
Optical Emission ◽  
Balmer Series ◽  
Boltzmann Plot ◽  
White Dwarf Stars ◽  
Peak Separation ◽  
Atomic Lines

This work communicates a review on Balmer series hydrogen beta line measurements and applications for analysis of white dwarf stars. Laser-induced plasma investigations explore electron density and temperature ranges comparable to white dwarf star signatures such as Sirius B, the companion to the brightest star observable from the earth. Spectral line shape characteristics of the hydrogen beta line include width, peak separation, and central dip-shift, thereby providing three indicators for electron density measurements. The hydrogen alpha line shows two primary line-profile parameters for electron density determination, namely, width and shift. Both Boltzmann plot and line-to-continuum ratios yield temperature. The line-shifts recorded with temporally- and spatially- resolved optical emission spectroscopy of hydrogen plasma in laboratory settings can be larger than gravitational redshifts that occur in absorption spectra from radiating white dwarfs. Published astrophysical spectra display significantly diminished Stark or pressure broadening contributions to red-shifted atomic lines. Gravitational redshifts allow one to assess the ratio of mass and radius of these stars, and subsequently, the mass from cooling models.

scholarly journals Machine Learning Prediction of Electron Density and Temperature from Optical Emission Spectroscopy in Nitrogen Plasma

Coatings ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1221
Author(s):  
Jun-Hyoung Park ◽  
Ji-Ho Cho ◽  
Jung-Sik Yoon ◽  
Jung-Ho Song
Keyword(s):  
Machine Learning ◽  
Electron Temperature ◽  
Real Time ◽  
Electron Density ◽  
Emission Spectroscopy ◽  
Optical Emission Spectroscopy ◽  
Optical Emission ◽  
Plasma Parameters ◽  
Plasma Nitridation

We present a non-invasive approach for monitoring plasma parameters such as the electron temperature and density inside a radio-frequency (RF) plasma nitridation device using optical emission spectroscopy (OES) in conjunction with multivariate data analysis. Instead of relying on a theoretical model of the plasma emission to extract plasma parameters from the OES, an empirical correlation was established on the basis of simultaneous OES and other diagnostics. Additionally, we developed a machine learning (ML)-based virtual metrology model for real-time Te and ne monitoring in plasma nitridation processes using an in situ OES sensor. The results showed that the prediction accuracy of electron density was 97% and that of electron temperature was 90%. This method is especially useful in plasma processing because it provides in-situ and real-time analysis without disturbing the plasma or interfering with the process.

Inductively Coupled Plasma Optical Emission Spectroscopy Determination of Trace Element Composition of Argan Oil

2010 ◽  
Vol 16 (1) ◽  
pp. 65-71 ◽  
Author(s):  
A. Gonzálvez ◽  
M.E. Ghanjaoui ◽  
M. El Rhazi ◽  
M. de la Guardia
Keyword(s):  
Trace Element ◽  
Inductively Coupled Plasma ◽  
Emission Spectroscopy ◽  
Optical Emission Spectroscopy ◽  
Limit Of Detection ◽  
Optical Emission ◽  
Inductively Coupled ◽  
Argan Oil ◽  
Plasma Optical Emission Spectroscopy

A methodology based on inductively coupled plasma optical emission spectroscopy (ICP-OES) after microwave assisted acid digestion has been developed to determine the trace element content of Moroccan argan oil. Limit of detection values equal or lower than few mg/kg were obtained for all elements under study. To assure the accuracy of the whole procedure, recovery studies were carried out on argan oil samples spiked at different concentration levels from 10 to 200 µg/L. Quantitative average recovery values were obtained for all elements evaluated, demonstrating the suitability of this methodology for the determination of trace elements in argan oil samples. Aluminum, calcium, chromium, iron, potassium, lithium, magnesium, sodium, vanadium and zinc were quantitatively determined in Moroccan argan oils being found that their concentration is different of that found in other edible oils thus offering a way for authentication and for the evaluation of possible adulterations.

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