The Dust-Gas Fireball as a Special Form of the Electric Erosive Discharge Afterglow

Conditions for non-stationary discharge initiation into "burning-through" mode

The special form of an electric discharge - "burn-through" in regard to the ball lightning problem has been considered. Having been carried out within closed volume, this mode of erosive discharge has shown the series of clear differences consisting in the high gas density, formation of the metal-polymer aerogel, the percolating current and unusual features of plasma's exhaust. The conditions for its stable origination and the main stages of the discharge process have been ascertained.

Interplay of transitions between oscillations with emergence of fireballs and quantification of phase coherence, scaling index in a magnetized glow discharge plasma of toroidal assembly

Interplay of transition of floating potential fluctuations in a glow discharge plasma in the toroidal vacuum vessel of SINP tokamak has been observed. With variation in the strength of the vertical and toroidal magnetic fields, regular and inverted relaxation oscillations as well as sinusoidal oscillations are observed with the slow and fast time scale of the relaxation oscillations reversing their nature at a high value of vertical magnetic field strength. However for small value of toroidal magnetic field the transitions follow relaxation $\rightarrow$ chaotic oscillations with the chaotic n…

The peculiarities of near-cathode processes in air discharge at atmospheric pressure

Formation of near-cathode plasma at the instant of breakdown of the air gap was studied by the methods of picosecond laser probing. It was demonstrated that 1-2 ns after a sharp rise of the current through the discharge gap dense plasma clots with Ne~10^20 cm^-3 and dNe/dx ~ 10^24 cm^-4 are formed on the cathode surface. It was shown that these highly ionized regions lead to initiation and development of the spark channel originating from the cathode. We propose that the observed formations correspond to erosive plasma formed from the cathode material.

Investigation of Space-Time Structure of the Discharge with an Electrolytic Anode and Face-Type, Air Half-Space Directed Cathode (Gatchina's Discharge)

Despite of its limited capabilities for ball-lightning modeling, the chemically active dust plasma of electric discharges is a very interesting physical object. Gatchina's discharge, which gives a possibility to study the dust-gas fireball, represents a complex non-stationary process, combining the creation and the destruction of relatively long-living high-enthalpy microscopic states with non-ideal dust plasma and with a gas-dynamic form, resulting in appearance of a spherical luminous object. In the present work we studied spatial structure of the discharge and its dynamics with the help of …

Mechanism behind self-sustained oscillations in direct current glow discharges and dusty plasmas

An alternative explanation to the mechanism behind self-sustained oscillations of ions in direct current (DC) glow discharges is provided. Such description is distinguished from the one provided by the fluid models, where oscillations are attributed to the positive feedback mechanism associated with photoionization of particles and photoemission of electrons from the cathode. Here, oscillations arise as consequence of interaction between an ion and the surface charges induced by it at the bounding electrodes. Such mechanism provides an elegant explanation to why self-sustained oscillations occ…

土卫六电离层中的尘埃等离子体相互作用：对气相成分的反馈

Interaction dust-plasma in Titan's ionosphere: feedbacks on the gas phase composition

本研究通过THETIS实验模拟土卫六电离层等离子体与气溶胶类似物的相互作用，发现N2-H2等离子体物种侵蚀气溶胶，导致气相中生成HCN等含氮物种，并影响气溶胶结构，揭示了非均相化学过程对土卫六大气成分的反馈作用。