[en] Method for measuring initial gas concentration in light lines by the rayleigh scattering is proposed and realized. high spatial resolution and sensitivity are peculiar features of this method. Local density heterogeneities, which could not be determined by interferometry, were registered by this method in stand experiments. Methodology for measuring initial particles density in light gaseous liners by the rayleigh scattering is describe comparison of this method with the interferometry method is carried out. Application of the Rayleigh scattering of the excimer (Xe Cl) laser for diagnostics of hole cylindrical gas jets, used in multiple experiments on magnetic implosion of light current-carrying shells, is demonstrated