  Interpretation of Doppler-Shift spectroscopy measurement of neutral beams
species content requires an assumption about distribution of populations of
thin structure of excited state (hydrogen n=3). In the paper several effects
caused mixing of sublevel population are discussed and correction factors for
different models of thin structure population are calculated. Such mixing can
lead to tens percent uncertainty of results of measurements of beam species
content. A possible way for experimental verification of sublevel population
mixing is proposed.
