The decay of the plasma produced by a freely localized microwave discharge

Abstract

A freely localized discharge is excited by a powerful microwave beam in argon, hydrogen and nitrogen. All processes of gas discharge production, maintenance and decay are volumetric in nature. The plasma decay is determined by diagnostic microwave beam attenuation. In the initial post-discharge stage the decay is close to an exponential law in nitrogen and hydrogen and to a linear law in argon. The decay adheres to the `recombinational' law only during the final stage of relaxation. Possible mechanisms for such behaviour are discussed.

Kinetics and Spectroscopy of Low Temperature Plasmas

“…By multiplying both members of the Boltzmann equation by 4 v 2 e and integrating over the whole velocity space, we obtain the continuity equation as in (6.66) dn e dt D se O 2 n e D n e < rec >; (6.85) but here instead of the term for secondary electron production by electron impact ionization, which can be neglected in the afterglow, we include a term for electronion recombination with the frequency rec . This term plays an important role in the final stages of the afterglow (Gritsinin et al 1996) when the electron and ion densities decay altogether with the same rate. This decay occurs according to the electron-ion volume recombination law 1=n e .t/ ' t (see Exercise 6.6).…”

“…Neglecting the dependence of D se on n e given by equation ( This equation can be integrated giving (Borysow and Phelps 1994) (ii) On the other hand, when only electron-recombination exists, we easily obtain (Gritsinin et al 1996) n e .0/ n e .t/ D 1 C˛n e .0/ t :…”

Presence of Space Charge Fields

“…(ii) On the other hand, when only electron-recombination exists, we easily obtain (Gritsinin et al 1996) n e .0/ n e .t/ D 1 C˛n e .0/ t :…”

“…This term plays an important role in the final stages of the afterglow (Gritsinin et al 1996) when the electron and ion densities decay altogether with the same rate. This decay occurs according to the electron-ion volume recombination law 1=n e .t/ ' t (see Exercise 6.6).…”

Особенности Формирования Нитевидной Структуры Микроволнового Разряда В Потоке Аргона

“…Микроволновые разряды высокого давления имеют неоднородную пространственную структуру [15][16][17][18][19][20][21][22][23][24][25]. Зачастую она определяется наличием в плазменном объеме тонких нитевидных каналов, ориентированных преимущественно вдоль электрического поля волны.…”