  A semi-phenomenological model of a many-particle system of 4He atoms is
proposed, in which a helium atom is considered as a complex consisting of a
nucleus and a bound pair of electrons in the singlet state. At zero
temperature, there are two Bose-Einstein condensates of particles with opposite
charges, namely, a condensate of positively charged nuclei and a condensate of
negatively charged electron pairs. It is shown that in such a system there
exist two excitation branches: sound and optical. On the basis of this model an
interpretation of experiments on the study of the eltctrical activity of
superfluid heliun is proposed. The frequency at which the resonant absorption
of a microwave radiation is observed is interpreted as a gap in the optical
branch. It is shown that the distribution of the electric potential in a
standing wave in a resonator is similar to that observed experimentally.
