An experimental investigation of partial LTE for lower excited levels of Ar(I) in a wall-confined, argon arc plasma

Shindo, Haruo; Imazu, Shingo

doi:10.1016/0022-4073(80)90121-1

Cited by 15 publications

(3 citation statements)

References 10 publications

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“…As can be seen in figure 5, the temperature obtained from the absolute line method decreases faster than do those obtained by other methods whereas in figure 6 for lower pressures the decrease with radius is almost the same as those for other methods. This is probably due to the fact that resonance radiation is still dominant in populating the first excited states, as suggested by the population distribution versus electron density data of Shindo and Imazu [24]. For lower pressure values, there is no agreement among the values of temperature and electron density deduced from the various methods.…”

Section: Resultsmentioning

confidence: 95%

The effect of pressure on a plasma plume: temperature and electron density measurements

Singh

Razafinimanana

Gleizes

1998

J. Phys. D: Appl. Phys.

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Measurements of temperature and electron number density measurements have been carried out on a plasma plume under various pressure conditions (p = 1-0.3 bar) using emission spectroscopy. The anode nozzle used does not generate a shock wave or an expansion-compression zone. Ar- (1%) is used as the plasma gas. Temperature values are obtained from various lines of neutral argon. Electron number densities are obtained from the Stark-effect broadening of the 486.1 nm H line and the continuum measurements. Measurements of temperature and density profiles reveal the general features of a low-pressure plasma jet, namely relatively low temperature and long heating zone of the expanded jet. The LTE criterion is satisfied at higher pressures ( bar). Deviations from ionization equilibrium occur at lower pressure. The variation of excited neutral argon and states has been studied for lower pressures. tends to be overpopulated compared with .

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Section: Resultsmentioning

confidence: 95%

The effect of pressure on a plasma plume: temperature and electron density measurements

Singh

Razafinimanana

Gleizes

1998

J. Phys. D: Appl. Phys.

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“…All these states are radiatively coupled to higher levels formed from the 3p 5 4p 1 configuration and can be observed in absorption between 700 and 850 nm [5]. Examples of such studies in inductively [5][6][7][8][9][10][11] and capacitively [12,13] coupled reactors, arcjets [14,15] and glow discharges [3,16,17] have been reported, with concentrations in the range of 10 9 -10 12 cm −3 . Wherever populations of both metastable and radiative states have been measured [3,8,12] they are found to be either of similar concentrations at high pressures (300-500 Torr) [8] or the metastables are approximately an order of magnitude larger than the radiative states at lower pressures (0.05-1 Torr) [3,12].…”

Section: Introductionmentioning

confidence: 98%

“…Examples of such studies in inductively [5][6][7][8][9][10][11] and capacitively [12,13] coupled reactors, arcjets [14,15] and glow discharges [3,16,17] have been reported, with concentrations in the range of 10 9 -10 12 cm −3 . Wherever populations of both metastable and radiative states have been measured [3,8,12] they are found to be either of similar concentrations at high pressures (300-500 Torr) [8] or the metastables are approximately an order of magnitude larger than the radiative states at lower pressures (0.05-1 Torr) [3,12]. In another study [11] the metastables are found to dominate only at pressures below 10 mTorr and have concentrations comparable to the radiative states for pressures as low as 50 mTorr.…”

Section: Introductionmentioning

confidence: 99%

Diode laser measurements of the Ar 3p⁵4s¹excited states in an inductively coupled RF plasma

Bakowski¹,

Hancock²,

Peverall³

et al. 2005

J. Phys. D: Appl. Phys.

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Diode laser absorption spectroscopy has been used to study the four lowest energy excited states of atomic argon (1s2–1s5) arising from the 3p54s1 electronic configuration and produced in an inductively coupled RF discharge. Three of the states (1s2, 1s4 and 1s5) were detected using wavelength modulation spectroscopy with diode laser radiation in the wavelength range 425–430 nm, obtained by frequency doubling the output of a near infrared diode laser in a KNbO3 crystal. The 1s3 state was probed using direct absorption spectroscopy with the fundamental output of a diode laser operating at 795 nm. The 1s5 state dominates the total population of this manifold with a proportion of around 48%, which is essentially independent of plasma power and pressure. Translational temperatures varied with power but were essentially pressure independent. For example, at 20 mTorr total pressure and 400 W applied power, the temperature was found to be 384 ±15 K. The variations in concentrations of all four 1sn states with plasma power and pressure are reported and suggests that a statistical equilibrium between them has been established. The results are rationalized by utilizing a simple kinetic model, to determine the dominant production (electron impact excitation from the ground state) and loss (intra-manifold quenching and radiative decay) processes. Fast redistribution of population in the states, mainly via electron impact excitation to higher lying electronic states and subsequent radiative decay back down, in combination with modified radiative rates for the two radiative states as a consequence of radiation imprisonment, can partially account for the observed relative trends.

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Number density and temperature measurements obtained using sensitive diode laser spectroscopy in an argon plasma

et al. 2005

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An experimental investigation of partial LTE for lower excited levels of Ar(I) in a wall-confined, argon arc plasma

Cited by 15 publications

References 10 publications

The effect of pressure on a plasma plume: temperature and electron density measurements

The effect of pressure on a plasma plume: temperature and electron density measurements

Diode laser measurements of the Ar 3p⁵4s¹excited states in an inductively coupled RF plasma

Number density and temperature measurements obtained using sensitive diode laser spectroscopy in an argon plasma

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An experimental investigation of partial LTE for lower excited levels of Ar(I) in a wall-confined, argon arc plasma

Cited by 15 publications

References 10 publications

The effect of pressure on a plasma plume: temperature and electron density measurements

The effect of pressure on a plasma plume: temperature and electron density measurements

Diode laser measurements of the Ar 3p54s1excited states in an inductively coupled RF plasma

Number density and temperature measurements obtained using sensitive diode laser spectroscopy in an argon plasma

Contact Info

Product

Resources

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Diode laser measurements of the Ar 3p⁵4s¹excited states in an inductively coupled RF plasma