Aleksandr Grigorievich Litvak

On the possibility of current drive in tokamaks by Bernstein modes

Abstract Current drive in a tokamak by electrostatic electron Bernstein waves is investigated. It is shown that a sufficiently large refractive index of these waves may result in regimes of rf power dissipation in which the effect of electron trapping into “banana” orbits will be essentially diminished. Besides, a stronger (as compared with O- and X-modes) absorption of electrostatic electron Bernstein modes results in an rf power input into more energetic electrons which is also favourable for the increase of the current drive efficiency.

Modeling of plasma chemical processes in the artificial ionized layer in the upper atmosphere by the nanosecond corona discharge

Abstract The plasma chemical processes in the corona discharge formed in air by a series of high voltage pulses of nanosecond duration are investigated experimentally. The experimental conditions (reduced electric field, duration and repetition frequency of the pulses, gas pressure in the chamber) modeled the regime of creation of the artificial ionized layer (AIL) in the upper atmosphere by a nanosecond microwave discharge. It was found that in a nanosecond microwave discharge predominantly generation of ozone occurs, and that the production of nitrogen dioxide is not large. The energy expenditures for the generation of one O 3 molecule were about 15 eV. On the basis of the experimental results the prognosis of the efficiency of ozone generation in AIL was made.