Expanding Plasma Region of an Inductively Driven Hydrogen Discharge

The spatial distribution of the plasma parameters - electron density and temperature as well as plasma and floating potentials - in the region of plasma expansion of an inductively driven low-pressure discharge in hydrogen is studied by probe diagnostics. Electron cooling and a decrease of the electron density with formation of regions with different axial gradients are outlined as basic features of the expanding plasmas. Thermal conductivity and electron energy flux from the driver are considered to be responsible for the plasma behavior at its expansion. The role of the thermal diffusion in the formation of the axial profile of the plasma density is also shown.