Correlation between spectroscopic and laser scattering techniques in investigation of REB-driven turbulence

Observation of turbulent microfields by means of the Stark spectroscopy is in general use in the experiments on collective interaction of electron beams with plasmas. The results of spectroscopic investigation of turbulence excited by a high current relativistic electron beam (REB) are compared with the spectra of turbulence obtained by laser scattering. We employ both the CO2 - laser scattering for measurements of the turbulence spectra and scattering of the 2nd harmonic of the Nd-laser for estimation of the turbulence level. The typical beam and plasma parameters are the same as those in previous experiments[1](n^∼ 10¹⁵cm⁻³, nb/np ^∼ 10⁻³, B=1−4 T, tb=100−200 ns). The electric field of high frequency (HF) turbulence is found from the profiles of hydrogen Hα. line. For the Stark measurements we used the laser absorption technique that provided a 0.007 nm spectral resolution in 1024 channels.