Measurement of time evolution of plasma electron component parameters on the Ogra-4 device by the Thomson scattering method

Measurements of time evoluition of electron distribution function in the ''Ogra-4'' device are described. Measurements were conducted with the use of laser diagnostics complex, operating in pulse-periodic conditions. Time evolution of plasma electron component density and energy distribution of electrons was measured. The presence of intense oscillations of plasma density during the ''Ogra-4'' device operation without injection of neutrals is shown. Accumulation of two groups of cold electrons with energies of tens and hundreds of electron-volt take s place in the center of the trap after injection initiation. It is expained consistently by formation of the positive potential during accumulation of hot ions, confined by magnetic field. Thus, Thomson scattering measuremet provided data on accumulation of hot ion component