scholarly journals Measurement of Stark Halfwidths of Spectral Lines of Ionized Oxygen and Silicon Emitted from T-tube Plasma

Atoms ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 8
Author(s):  
Lazar Gavanski

The analysis of experimental Stark halfwidths of spectral lines of singly ionized oxygen and silicon and double ionized silicon is presented in this work. The considered spectral lines were emitted from plasma generated in an electromagnetically driven T-tube, with an electron temperature of 15,000 K and electron density of 1.45 × 1023 m−3. The obtained Stark halfwidths were compared to experimental values given by other authors. In addition, all experimental values were compared to theoretical values. These data are useful for diagnostics of laboratory and astrophysical plasmas as well as verifying theoretical models.

2018 ◽  
Vol 7 (3) ◽  
pp. 1177 ◽  
Author(s):  
Sabah N. Mazhir ◽  
Mohammed K. Khalaf ◽  
Sarah K. Taha ◽  
Hussein K . Mohsin

This paper discusses applying different voltages and pressure in the presence of silver target and argon gas to produce plasma. Home-made dc magnetron sputtering system was used to produce glow discharge plasma. The distance between two electrodes is 4 cm. Gas used to produce plasma is argon that flows inside the chamber with flow rate 40 sccm. Intensity of spectral lines, electron temperature and electron density were studied. The results show that the intensity of spectral lines increases with the increase of the working pressure and applied voltage. Electron temperature increases by the increase of applied voltage but decreases with the increase of working pressure, while electron density decreases with the increase of applied voltage and increases with the increase of working pressure. This research demonstrates a new low cost approach to start producing high corrosion resistance materials.  


1974 ◽  
Vol 29 (11) ◽  
pp. 1690-1691
Author(s):  
H. Mauderer ◽  
G. Schmid

The properties of a low-pressure non-thermal He-plasma jet have been investigated. The gas temperature was obtained from the population densities of high excited He-levels. The electron density was determined both from the Stark-effect broadening of some He-lines and from the intensities of some forbidden transitions. The radial distribution of electron temperature was found by comparing the computed population densities of the He 31P level with the experimental values.


2018 ◽  
Vol 16 (36) ◽  
pp. 113-122
Author(s):  
Ali A-K. Hussain

In this work, the spectra of plasma glow produced by Nd:YAG laser operated at 1.064 μm on Al-Mg alloys with same molar ratio samples in air were analyzed by comparing the atomic lines of aluminum and magnesium with that of strong standard lines. The effect of laser energies on spectral lines, produced by laser ablation, were investigated using optical spectroscopy, the electron density was measured utilizing the Stark broadening of magnesium-aluminum lines and the electron temperature was calculated from the standard Boltzmann plot method. The results that show the electron temperature increases in magnesium and aluminum targets but decreases in magnesium: aluminum alloy target, also show the electron density increase all the aluminum, magnesium and mix both them, It was found that the lines intensities at different laser peak powers increase when the laser peak power increases then decreases when the power continues to increase.


1973 ◽  
Vol 9 (1) ◽  
pp. 77-88 ◽  
Author(s):  
W. A. Cilliers ◽  
J. D. Hey ◽  
J. P. S. Rash

At plasma densities lower than about 1018 cm-3, strictly speaking, the LTE model cannot be used when the electron temperature is calculated from measured spectral line intensity ratios. In this work a number of nitrogen spectral lines were studied at an electron density of about 1016 cm-3, and the results are discussed with reference to the LTE and semi-coronal models. A method is suggested for analyzing line intensity ratio data from plasmas in the semi-coronal regime.


2000 ◽  
Vol 18 (10) ◽  
pp. 1257-1262 ◽  
Author(s):  
A. V. Pavlov ◽  
T. Abe ◽  
K.-I. Oyama

Abstract. We present a comparison of the electron density and temperature behaviour in the ionosphere and plasmasphere measured by the Millstone Hill incoherent-scatter radar and the instruments on board of the EXOS-D satellite with numerical model calculations from a time-dependent mathematical model of the Earth's ionosphere and plasmasphere during the geomagnetically quiet and storm period on 20–30 January, 1993. We have evaluated the value of the additional heating rate that should be added to the normal photoelectron heating in the electron energy equation in the daytime plasmasphere region above 5000 km along the magnetic field line to explain the high electron temperature measured by the instruments on board of the EXOS-D satellite within the Millstone Hill magnetic field flux tube in the Northern Hemisphere. The additional heating brings the measured and modelled electron temperatures into agreement in the plasmasphere and into very large disagreement in the ionosphere if the classical electron heat flux along magnetic field line is used in the model. A new approach, based on a new effective electron thermal conductivity coefficient along the magnetic field line, is presented to model the electron temperature in the ionosphere and plasmasphere. This new approach leads to a heat flux which is less than that given by the classical Spitzer-Harm theory. The evaluated additional heating of electrons in the plasmasphere and the decrease of the thermal conductivity in the topside ionosphere and the greater part of the plasmasphere found for the first time here allow the model to accurately reproduce the electron temperatures observed by the instruments on board the EXOS-D satellite in the plasmasphere and the Millstone Hill incoherent-scatter radar in the ionosphere. The effects of the daytime additional plasmaspheric heating of electrons on the electron temperature and density are small at the F-region altitudes if the modified electron heat flux is used. The deviations from the Boltzmann distribution for the first five vibrational levels of N2(v) and O2(v) were calculated. The present study suggests that these deviations are not significant at the first vibrational levels of N2 and O2 and the second level of O2, and the calculated distributions of N2(v) and O2(v) are highly non-Boltzmann at vibrational levels v > 2. The resulting effect of N2(v > 0) and O2(v > 0) on NmF2 is the decrease of the calculated daytime NmF2 up to a factor of 1.5. The modelled electron temperature is very sensitive to the electron density, and this decrease in electron density results in the increase of the calculated daytime electron temperature up to about 580 K at the F2 peak altitude giving closer agreement between the measured and modelled electron temperatures. Both the daytime and night-time densities are not reproduced by the model without N2(v > 0) and O2(v > 0), and inclusion of vibrationally excited N2 and O2 brings the model and data into better agreement.Key words: Ionosphere (ionospheric disturbances; ionosphere-magnetosphere interactions; plasma temperature and density)  


2020 ◽  
Vol 498 (2) ◽  
pp. 2068-2074 ◽  
Author(s):  
J Manrique ◽  
D M Díaz Pace ◽  
C Aragón ◽  
J A Aguilera

ABSTRACT We have measured the Stark widths and shifts of V II spectral lines in the wavelength range 2000–4200 Å belonging to 75 multiplets. The spectra are emitted by laser-induced plasmas generated from fused glass discs prepared by borate fusion. The electron density and temperature are in the ranges (0.72–6.5) × 1017 cm−3 and (11 000–14 900) K, respectively. To avoid self-absorption, we have used seven samples with vanadium concentrations selected by the CSigma graph methodology. This has allowed to include strong and weak lines in the study, including resonance and forbidden lines. The experimental widths and shifts are compared with theoretical values available in the literature.


2018 ◽  
Vol 73 (2) ◽  
pp. 203-213 ◽  
Author(s):  
Jhonatha R. dos Santos ◽  
Jonas Jakutis Neto ◽  
N. Rodrigues ◽  
M.G. Destro ◽  
José W. Neri ◽  
...  

In this work, we suggest a methodology to determine the impact parameter for neutral dysprosium emission lines from the characterization of the plasma generated by laser ablation in a sealed chamber filled with argon. The procedure is a combination of known consistent spectroscopic methods for plasma temperature determination, electron density, and species concentration. With an electron density of 3.1 × 1018 cm–3 and temperature close to 104 K, we estimated the impact electron parameter for nine spectral lines of the neutral dysprosium atom. The gaps in the impact parameter data in the literature, mainly for heavy elements, stress the importance of the proposed method.


Coatings ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1221
Author(s):  
Jun-Hyoung Park ◽  
Ji-Ho Cho ◽  
Jung-Sik Yoon ◽  
Jung-Ho Song

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.


2019 ◽  
Vol 14 (31) ◽  
pp. 205-214
Author(s):  
Ali A-K. Hussain

In this work, the spectra for plasma glow produced by pulseNd:YAG laser (λ=532 and 1064nm) on Ag:Al alloy with same molarratio samples in distilled water were analyzed by studying the atomiclines compared with aluminum and silver strong standard lines. Theeffect of laser energies of the range 300 to 800 mJ on spectral lines,produced by laser ablation, were investigated using opticalspectroscopy. The electron temperature was found to be increasedfrom 1.698 to 1.899 eV, while the electron density decreased from2.247×1015 to 5.08×1014 cm-3 with increasing laser energy from 300to 800 mJ with wavelength of 1064 nm. The values of electrontemperature using second harmonic frequency are greater than of1064 nm, which increased from 2.405 to 2.444 eV, while the electrondensity decreased from 2.210×1015 to 1.516×1015 cm-3 withincreasing laser energy for the same energy range.


2019 ◽  
Vol 13 (27) ◽  
pp. 76-82
Author(s):  
Kadhim A. Aadim

Low-pressure capacitively coupled RF discharge Ar plasma has been studied using Langmuir probe. The electron temperature, electron density and Debay length were calculated under different pressures and electrode gap. In this work the RF Langmuir probe is designed using 4MHz filter as compensation circuit and I-V probe characteristic have been investigated. The pressure varied from 0.07 mbar to 0.1 mbar while electrode gap varied from 2-5 cm. The plasma was generated using power supply at 4MHz frequency with power 300 W. The flowmeter is used to control Argon gas flow in the range of 600 standard cubic centimeters per minute (sccm). The electron temperature drops slowly with pressure and it's gradually decreased when expanding the electrode gap. As the gas pressure increases, the plasma density rises slightly at low gas pressure while it drops little at higher gas pressure. The electron density decreases rapidly with expand distances between electrodes.


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