  The ground state properties and low-lying excitations of a (quasi)
one-dimensional system of longitudinally confined interacting bosons are
studied. This is achieved by extending Haldane's harmonic-fluid description to
open boundary conditions. The boson density, one-particle density matrix, and
momentum distribution are obtained accounting for finite-size and boundary
effects. Friedel oscillations are found in the density. Finite-size scaling of
the momentum distribution at zero momentum is proposed as a method to obtain
from the experiment the exponent that governs phase correlations. The strong
correlations between bosons induced by reduced dimensionality and interactions
are displayed by a Bijl-Jastrow wave function for the ground state, which is
also derived.
