  We present a systematic study of the Green functions of a one-dimensional gas
of impenetrable anyons. We show that the one-particle density matrix is the
determinant of a Toeplitz matrix whose large N asymptotic is given by the
Fisher-Hartwig conjecture. We provide a careful numerical analysis of this
determinant for general values of the anyonic parameter, showing in full
details the crossover between bosons and fermions and the reorganization of the
singularities of the momentum distribution function.
  We show that the one-particle density matrix satisfies a Painleve VI
differential equation, that is then used to derive the small distance and large
momentum expansions. We find that the first non-vanishing term in this
expansion is always k^{-4}, that is proved to be true for all couplings in the
Lieb-Liniger anyonic gas and that can be traced back to the presence of a delta
function interaction in the Hamiltonian.
