Density and polarizability of liquid 4He

The temperature dependence of the density of liquid helium is measured in the temperature range from 1.63 to 4.2 K. Instead of the pycnometric technique employed earlier, we use the method of buoyancy. The applicability of the method and of the equipment used for measurements of this kind is discussed. A good agreement is observed with the results obtained by other authors. The results of measurements of the temperature dependence of density ρ and dielectric constant ϵ are used for calculating the dependence of the polarizability A of liquid 4He on temperature and density. These results point towards a complex nature A(T) and A(ρ) dependences, which are found to be mutually correlated.