Structure functions of many-boson system with regard for direct three- and four-particle correlations

الأصل · EN

On the basis of the expression for the density matrix of interacting Bose particles in the coordinate representation with regard for the direct three- and four-particle correlations [I.O.Vakarchuk and O.I.Hryhorchak, J.Phys.Stud.3, 3005 (2009)], the two-, three-, and four-particle structure factors of liquid ⁴He in a wide temperature interval were calculated in the approximation "one sum over the wave vector".In the low-temperature limit, the expression obtained for the two-particle structure factor transforms into the well-known one.In the high-temperature limit, the expressions for the two-, three-, and four-particle structure factors are reduced to those for the ideal Bose gas.The results obtained can be applied to calculations of the thermodynamic functions of liquid ⁴He and to the determination of the temperature dependence of the first-sound velocity in a many-boson system.