This paper describes the use of Optical Emission Spectroscopy (OES) to measure electron densities and temperatures in non-equilibrium plasmas. The ways interpret relative line-intensities neutral argon atoms are evaluated based upon a collisional-radiative model including atomic collisional processes. A conversion from an excitation temperature determined line intensities assuming Boltzmann population distribution thermal range 1–4 eV density 1010–1012 cm–3 is given. Procedures obtain Te Ne...

The present paper describes a spectroscopic method for determining the electron temperature Te and density Ne in argon plasmas on basis of collisional-radiative model argon. We measured positive column an dc discharge by developed, compared them with those obtained Langmuir probe. results agreed roughly However, limitation our obtaining was found.

We measured the band spectra (first and second positive systems) of nitrogen molecule to examine vibrational rotational temperatures CΠ3 BΠ3 states by optical emission spectroscopy. compared experimentally calculated determine those generated plasma. a microwave discharge plasma in cylindrical quartz tube (26mm inside diameter) with pressure 0.5–1.0Torr. The frequency was 2.45GHz output power set at 600W. It found that Tv≈0.5–0.7eV Tr≈0.07–0.15eV (v=7, 8, 9), whereas Tv≈0.65–0.9eV...

Population densities of excited states argon atoms are theoretically examined for ionizing plasma in a state nonequilibrium under atmospheric pressure from the viewpoint elementary processes with collisional radiative model. The dependence populations on electron and gas temperatures is discussed. Two density regimes found, which distinguished by population depopulation mechanisms problem. When impact excitation frequency or lower than atomic one, considered as low to estimate processes....

Abstract The electron temperature T e and density N of atmospheric-pressure non-equilibrium dielectric barrier discharge argon (Ar) plasma are measured with optical emission spectroscopy. Continuum due to bremsstrahlung is applied the analysis spectrometric system in visible wavelength range calibrated absolutely. assumption Maxwellian energy distribution function (EEDF) results ≃ 0.29 eV 1.1 × 10 16 cm −3 , whereas Druyvesteyn EEDF leads result 0.79 1.4 14 . To confirm validity these...

Abstract Partial arbitrary electron energy distribution function (EEDF) results for cold atmospheric-pressure plasma are reported. The EEDF is obtained using the visible bremsstrahlung inversion (VBI) method. This machine learning method requires only optical emission spectroscopy (OES) measurement and a momentum transfer cross section to determine partial EEDF. Numerical of pure-argon dielectric barrier discharge dataset with changing peak-to-peak voltage helium–argon mixture ratio...

We generate a microwave discharge nitrogen plasma using rectangular waveguide and quartz tube (30 mm i.d.) inserted along the vector of electric field, with an adjustable short-circuited plunger. The typical conditions used are as follows: frequency 2.45 GHz, input power 550 W, (99.5%) gas flow rate 0.01–1.6 l/min, pressure p =0.5–10 Torr. Electron temperature T e , density n measured double probe. Vibrational v is obtained from population vibrational exited states N 2 C 3 Π u by...

Abstract The plasma jet generation of reactive oxygen and nitrogen species (RONS) in solution is important biology, medicine, disinfection. Studies using a wide variety devices have been carried out for this purpose, making it difficult to compare the performance between devices. In study, we compared efficiency RONS deionized (DI) water 3.7-mm- 800-µm-sized helium (He) jets (hereafter mm-jet µm-jet, respectively) at different treatment distances times. was determined by considering total...

The gas temperature in plasma enhanced chemical-vapour-deposition is a key parameter to determine the properties of deposited films because it influences gas-phase reactions radicals and surface precursors. In this paper, we report measurement results determined from optical emission spectroscopy molecular spectra discuss heating growing film. It found that linearly increases with density surrounding wall temperature. dominated by collisions high-temperature molecules generated at high...

To understand the mechanism of surface processing using atmospheric-pressure nonequilibrium plasma jets, we measured vibrational and rotational temperatures in plasmas by optical emission spectroscopy. Plasma was excited a high-frequency pulsed power supply, gas mixture Ar (20 L/min) N2 (0.1 to 0.5 as gas, changing flow rate at an input 100 W frequencies 5 10 kHz. The were approximately 0.18 0.26 eV 0.21 0.28 eV, respectively. We also carried out polyethylene terephtalate film measure...

The dissociation degrees of N 2 and O are examined in a nitrogen–oxygen mixed microwave discharge plasma cylindrical quartz tube 26 mm inner diameter with pressure 0.5–1.0 Torr power 600 W by the actinometry method. We measured electron temperature density Langmuir double probe, while vibrational rotational temperatures first second positive bands were optical emission spectroscopy. Even when line intensity atomic nitrogen was weak partly coincided high-intensity band spectrum system due to...

A new method to determine the arbitrary electron energy distribution function (EEDF) from optical emission spectroscopic measurement in atmospheric-pressure plasma is introduced. The spectroscopy (OES) continuum spectrum, dominated by electron-neutral bremsstrahlung radiation, analyzed inspect usefulness of conventional OES range for EEDF determination. reconstructed radiation spectrum applying machine learning solve emissivity equation inversely. Through iterative statistical analysis,...

There are few reported cases in which the spatial distribution of spectral emission coefficients plasmas from tomographic optical spectroscopy measurements is analyzed based on a collisional-radiative model to diagnose electron temperature Te and density Ne. This study aimed at situ diagnosis process plasma. The radiance 18 lines-of-sight was measured simultaneously argon inductively coupled excited level number calculated obtained tomography calculations. three-dimensional Ne using levels...

In this study, the electron densities and temperatures in helium argon nonthermal atmospheric-pressure plasmas are obtained by continuum spectral analysis, a comparison is made to investigate factors that cause differences these two quantities. The irradiated onto floating copper disk. both plasmas, plasma plume formed with same length between edge of powered electrode surface disk, flow rate each neutral gas controlled obtain thermal pressure, which product density temperature. charge...

Abstract A robust method for determining the electron temperature and density of atmospheric-pressure non-equilibrium argon plasmas is reported. The methodology based on analysis continuum line spectra plasma. Assuming that energy distribution function (EEDF) expressed as a two-temperature generalized EEDF (GEEDF), gamma value GEEDF determined through grid search spectrum given by bremsstrahlung process, which minimizes mean-squared logarithmic error (MSLE). In addition, relationship between...

This study proposed a simple method to evaluate the spectral reflectance of inner wall vacuum chamber. A for calculating emission coefficients by taking chamber into account was proposed. Furthermore, plasma diagnosis based on optical spectroscopic (OES) measurement performed so as obtain radial dependence electron temperature Te and density Ne radio frequency inductively coupled Argon (Ar) applying collisional-radiative model radially resolved spectra Ar assuming axial symmetry. In...

We examined the vibrational and rotational temperatures of C 3 Π B states N 2 by optical emission spectroscopy. measured band spectra (first second positive systems) compared experimentally calculated to determine actual generated plasma. a microwave discharge nitrogen plasma in cylindrical quartz tube (26 mm i.d.) with pressure 0.5–1.0 Torr. The frequency was 2.45 GHz output power set at 600 W. It found that T v ≈0.5–0.7 eV r ≈0.07–0.15 ( =7, 8 9), whereas ≈0.65–0.9 ≈0.06–0.16 =0 1). also...

The effect of the electron energy distribution function (EEDF) on population excited states is investigated in He and Ar plasmas sustained by a 2.45 GHz microwave at discharge pressure 1–5 Torr. EEDF measured with Langmuir probe Druyvesteyn's method used as input parameter collisional-radiative (CR) model calculation. calculated density compared results optical emission spectroscopic measurement. Reasonable agreement found between them. It also confirmed that EEDFs was depleted energies...

It is crucial to measure the electron density (ne) and temperature (Te) for applications such as developing small helicon sources in plasma thrusters. Hence, this study developed a method based on an optical emission spectroscopic (OES) measurement without disturbance or contamination produced using argon gas. The collisional-radiative (CR) model was used describe excitation number function of ne Te. Each ratio surveyed From these results, contours two densities, i.e., energy levels, were...

With an aim to understand the mechanism of surface processing by atmospheric-pressure nonequilibrium discharge plasma jets, we measured vibrational and rotational temperatures in plasmas means optical emission spectroscopy (OES) measurement method. This paper focuses on OES method using a torch-shaped jet power supply consisting microwave (2.45-GHz) generator high-frequency (5.0-10-kHz) dc pulse supply, gas mixture Ar (8.0 L/min) N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Abstract The arbitrary electron energy distribution function (EEDF) of cold atmospheric-pressure plasma is determined from optical emission spectroscopy measurement. Using the electron-neutral bremsstrahlung-dominated continuum spectrum and relevant cross-section data, a partial EEDF can be reconstructed through reinforcement learning-based visible bremsstrahlung inversion method. From an argon dielectric barrier discharge (440–900 nm), with resolution 0.2 eV. resemblance between obtained...