Thymine and cytosine spectral characteristics in gas discharge

The spectral characteristics of the high-frequency part of the slow electromagnetic mode, specific for plasmas placed in an external d.c. electric field, as well as the features of the corresponding instability, are analysed for weakly ionized argon gas-discharge plasmas with E/n ranging from 25 to 150 Td, and with electron temperatures between 60000 and 70000 K. The analysis is based on the linear theory of perturbation, and the dynamics of the electrons is described by appropriately modified kinetic equations for the one-particle distribution function. Attention is focused on the collisional processes between electrons and neutrals, and both elastic and excitational collisions are taken into account. Apart from the ‘indirect’ collision effects (modifications of the form of the electron steady-state distribution function, evaluated here analytically, with the thermal motion of the neutrals included), their ‘direct’ influence (arising from perturbations of the collision integrals) is also significant in the electron temperature range considered. As a consequence of the ‘direct’ influence of inelastic collisions, in particular, the mode studied was found to exist in two distinctly separate wavelength ranges. The instability was found to develop only in the one corresponding to shorter wavelengths (below some 30 cm).

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Spectroscopic diagnostics of a high-frequency dielectric barrier discharge of atmospheric pressure in mixtures of cadmium diiodide vapor with neon and small additions of xenon

Journal of Technological and Space Plasmas ◽

10.31281/jtsp.v1i1.14 ◽

2020 ◽

Vol 1 (1) ◽

pp. 45-53

Author(s):

Antonina Malinina

Keyword(s):

Atmospheric Pressure ◽

High Frequency ◽

Discharge Plasma ◽

Barrier Discharge ◽

Spectral Characteristics ◽

Emission Spectra ◽

Gas Discharge ◽

Gas Discharge Plasma ◽

Excimer Molecules ◽

Multi Wavelength

Diagnostics of the emission spectra of a gas-discharge plasma of a barrier discharge of atmospheric pressure in mixtures of cadmium diiodide vapor with neon and small additions of xenon is carried out. A gas-discharge plasma was created and the components of the working mixture were excited by a high-frequency barrier discharge at a sinusoidal voltage pulse repetition rate of up to 140 kHz. Emission of exciplex molecules of cadmium monoiodide with a maximum emission at a wavelength of λ = 655 nm and xenon iodide with a maximum of radiation at wavelengths λ = 253 and λ = 320 nm, excimer molecules of iodine, lines of atoms of cadmium, iodine, neon and xenon was revealed. It was found that at temperatures of the mixtures under study above 150 0C, the predominance of radiation from exciplex molecules of cadmium monoiodide is observed. The reason for the increased brightness of the emission of exciplex molecules of cadmium monoiodide in mixtures of cadmium diiodide vapor with neon and xenon additive is established. The regularities in the spectral characteristics of radiation in the mixtures under study are discussed. A high-frequency barrier discharge of atmospheric pressure in mixtures of cadmium diiodide vapor with neon and xenon is of interest for creating a multi-wavelength excilamp in the UV and visible spectral ranges

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Spectral characteristics of gas discharge ion lasers on vapors of thallium and gallium

Optical Memory and Neural Networks ◽

10.3103/s1060992x16020028 ◽

2016 ◽

Vol 25 (2) ◽

pp. 118-122

Author(s):

I. G. Ivanov ◽

V. E. Privalov

Keyword(s):

Spectral Characteristics ◽

Gas Discharge ◽

Ion Lasers

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Characteristics of Radiation of High-Pressure Short-Arc Xenon Gas-Discharge Lamp

Herald of the Bauman Moscow State Technical University Series Instrument Engineering ◽

10.18698/0236-3933-2019-6-50-63 ◽

2019 ◽

pp. 50-63

Author(s):

S.V. Gavrish ◽

A.N. Kondratyev ◽

V.V. Loginov ◽

N.Yu. Petrenko ◽

S.G. Kireev

Keyword(s):

High Pressure ◽

Spatial Distribution ◽

Quartz Glass ◽

Cathode Spot ◽

Spectral Characteristics ◽

Gas Discharge ◽

Electrode Erosion ◽

Discharge Lamp ◽

Tungsten Layer ◽

Short Arc

The paper is devoted to the study of changes in characteristics of ultra-high pressure short-arc xenon lamps when a tungsten layer is sprayed onto the quartz shell, as a result of heating and local electrode erosion. The paper analyzes the mechanisms of phenomena occurring in the super-high pressure xenon discharge and the cathode spot, which affect the sputtering of the electrode material. The main negative effects of tungsten deposits appearing on the lamp shell inner surface are considered: a decrease in the optical transparency and mechanical strength of quartz glass, an increase of the bulb temperature, a change in spectral characteristics and spatial distribution of radiation of a gas-discharge lamp. The original method developed for studying the parameters of radiation of a gas-discharge lamp and based on the superposition of the optical axis of the photometer with the axis of the lamp passing through the cathode spot and the considered shell segment, transparent or sprayed, allowed us to compare radiation characteristics of the lamp without changing the plasma parameters. The thermodynamic analysis carried out within the research confirmed the absence of chemical interaction of tungsten layer with quartz glass. Spectral distribution of xenon discharge radiation in the visible and IR ranges is different for a transparent bulb and the bulb with a tungsten spot, which is due to the size of tungsten layer particles on the lamp bulb. A study of spatial distribution of radiation from a gas-discharge lamp showed a decrease in the intensity of radiation in a solid angle bounded by a tungsten spot. At the same time, in this region, there was observed an increase in the temperature of the quartz shell, leading to the appearance of a longitudinal gradient of the temperature field of the gas-discharge lamp.

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