Correlation functions of the one-dimensional Bose gas in the repulsive case

The one dimensional Bose gas is considered in the repulsive case. The ground state of the system is the Dirac sea with a finite density. The correlation function of the currents is presented in the form of the series, the n^th term being the contribution of n vacuum particles. In the strong coupling limit c → ∞ the n^th term decreases as c^-n. In the weak coupling limit c → 0 the series is also essentially simplified. The decomposition gives the uniform approximation in the distance between the currents. The arguments in favour of convergence of the series are given.