  We study the ground state one-body correlation function in the Lieb-Liniger
model. In the spectral representation, correlations are built from
contributions stemming from different excited states of the model. We aim to
understand which excited states carry significant contributions, specifically
focusing on the small energy-momentum part of the dynamic one-body function. We
conjecture that relevant excitations take form similar to two-spinon states
known from XXZ spin chain. We validate this hypothesis by numerical evaluation
of the correlator with ABACUS algorithm and by analytical computations in the
strongly interacting regime.
