A. Burdakov (Sp), Budker Institute of Nuclear Physics, Novosibirsk (Russia); A.V. Arzhannikov, V.T. Astrelin, V.T. Ivanov, I.A. Mekler, S.V. Polosatkin, V.V. Postupaev, A.F. Rovenskikh, A.F. Sinitsky, E.R. Zubairov, Budker Institute of Nuclear Physics, Novosibirsk (Russia)
The experimental study of heating and confinement of a dense (10^20-10^22 m^-3) plasma in 12-meter-long multiple mirror trap is carried out at the GOL-3 facility in Budker Institute of Nuclear Physics. Collective plasma heating by ~120 kJ (~8 microseconds) relativistic electron beam results in electron temperature ~2 keV at ~10^21 m-3 density. High electron temperature exists for ~10 microseconds. To this time ion temperature reaches ~2 keV. Ion temperature keeps at the high level during ~1 ms.
High power of plasma exhaust through the device end was used in the ITER-related studies of interaction of powerful plasma and hot electron streams with carbon materials. The energy yield to the target can be varied in the range of 0.5-3 MJ/m^2 that is similar to conditions of ITER ELM events. An important feature of GOL-3 facility is suitable broad electron spectrum which ranges from thermal electrons to ~1 MeV energies. Such spectrum results in correct monotonously decreasing dependence of volumetric energy release on the sample depth. High-energy fraction of GOL-3 electron spectrum enables to model the sample preheating to ~1500 deg. Regimes with large erosion of the armour material (e.g., graphite or CFC) and dust particles emission are possible. During the plasma heating stage (some microseconds) the surface of the target evaporates and dense carbon jet propagates along the magnetic field in the background hot plasma.