The dynamics of supersonic plasma flows interaction with the magnetic arch in a laboratory setup

The dynamics of the plasma deceleration process during the transversal injection in the tridimensional magnetic arch formed by magnetic coils is studied. The effect of the magnetic field lines deformation in the apex is experimentally observed when the plasma flow stops in the region where its ram pressure equals the magnetic pressure. The propagation direction of the plasma flow is changed as a result of plasma flow interaction with the magnetic arch. The plasma flow velocity along magnetic field lines is experimentally measured and is in a good agreement with numerical estimates of Alfven velocity. The transition layer is formed with a transverse size of the order of ionic inertial length as a result of the interaction of the plasma flow with the magnetic field. Non-thermal microwave emission of plasma is experimentally detected in the electron cyclotron frequency range during plasma deceleration process. The electromagnetic spectrum at frequencies of 1–2 GHz has been studied in detail.

Simultaneous injection of two counter-streaming plasma flows along the magnetic field of the arch leads to the magnetic field breakup in the apex of the arch. During this process, a non-thermal microwave emission is registered at a frequency which is proportional to the magnetic field strength in the apex of the magnetic arch. This observation proves the formation of a fraction of energetic particles during the collision of counter-propagating plasma flows in the magnetic arch.