Tude d'une d charge axiale haute fr quence

Abstract

A high power generator delivers r.f. current pulses of 4 μsec duration at a frequency of 2 Mc. It is used to produce an axial current of 18.6 kA peak amplitude in a plasma contained in a tube of 5 cm dia. and 42.5 cm length. The structure of the discharge is observed by means of framing and streak pictures. At pressure greater than 50 mtorr H2 one observes the formation of a luminous core which remains stable for the duration of the current flow. The electron temperature and mass flow velocity of the plasma are deduced from magnetic probe measurements of the diffusion of the alternating magnetic field. The electron temperature in an annular region surrounding the luminous core is about 6 eV. The measured flow velocity shows that an initial compression is followed by an expansion of the plasma.