[Back]

D. Brida, D. Tskhakaya:
"On Ion Sound Speed in a High Recycling Plasma Edge";
Contribution to Plasma Physics, 54 (2014), 4-6; 498 - 502.

The ion sound speed is derived from the propagation speed of small perturbations. For this purpose, we consider particle, momentum and energy conservation equations for the ions and Ohms law for the electrons. We find out that there exist three oscillation modes: two of them correspond to the waves propagating towards the wall and one propagating away from it. One of the modes propagating towards the wall and the mode propagating away from the wall are identified as sound waves. We demonstrate that for the plasma parameters corresponding to the high recycling regime the ion sound speed propagating towards the wall exceeds significantly the commonly given isothermal, or adiabatic sound speeds. Moreover, we show that there exists a layer in front of the wall, where the second mode propagating towards the wall has a positive growth rate. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Plasma edge;sound speed;high recycling plasma