Possibility of the helium abundance determination based on helioseismological data

The possibility of determination of the helium abundance in the solar envelope with the aid of the detailed analysis of the helioseismological data is considered. The peculiarity of the adiabatic gradient behaviour in the T∼100000 K region is depended on the helium abundance. The influence of such effects on the spectrum of the acoustic oscillations is studied with the aid of special function of observed frequencies β(ω). This function is related to the phase lag of the acoustic wave reflected from the surface. The peculiarity of the convective structure causes the sinusoidal disturbance of β(ω). The phase of sinusoidal component of β(ω) is used for determination of the helium abundance in the solar convective zone. The comparison of observed and theoretical functions β(ω) permits the helium abundance to be determined as the parameter of the solar envelope