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An extended current sheet characterized by two peculiarities was formed in a configuration with opposite magnetic fields in a laboratory plasma on a '0-pinch' device. First, development of the small scale turbulence leads to abnormal low sheet conductivity, through-sheet plasma diffusion and establishes the sheet thickness an order greater than the skin thickness c/tope (o)pe is electron plasma frequency). Second, there develops and quickly stabilizes in a sheet the magnetic force line reconnection. As a result, a stable neutral sheet has the complicated structure of a magnetic field, including closed magnetic loops elongated along the axis of the system. The neutral sheet plasma becomes intensively heated, probably due to ion-sound turbulence, while a group of accelerated electrons, which on the energy spectrum lead to a 'plateau' formation, are observed. The absence of any predominant direction is a typical feature for the motion of accelerated particles. The experimental data, obtained over a broad range of plasma densities and magnetic field values typical for the solar atmosphere, show that the antiparallel magnetic field turbulent dissipation could play an important role in the mechanism of solar energy release. The parameters of accelerated particles (energy e ~--4-12 keV, the energy content being 10-~-10 ~ of all the energy dissipated in a sheet) agree nicely with the data of astrophysical observations.

Abstract. This paper deals with the scattering of electromagnetic radiation during propagation through a plasma layer with developed Langmuir turbulence. The ordinary component is slightly lowered, while the extraordinary component undergoes the most effective scattering. This leads to a change in the polarization characteristics of the original radiation, namely: the extraordinarily polarized emission can undergo a substantial decrease and even the polarization sign can be changed. As a consequence the radiation increases its polarization degree in the ordinary mode. We performed calculations of the polarization of the radio emission propagating through a layer of turbulent plasma and examined the complex event that occurred on July 14, 2000; specifically, this event showed long-lasting emissions and the polarization varied both in time and in frequency range. Assuming that the variation of the polarization degree during the lifetime of the phenomenon is determined by the scattering from Langmuir turbulence, we obtained an estimate of the level of turbulence and of the magnetic field intensity in the emission region.

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