Zero temperature correlation functions for the impenetrable fermion gas

We calculate the long time and distance asymptotics of the one-particle correlation functions in the model of impenetrable spin 1/2 fermions in 1+1 dimensions. We consider the spin disordered zero temperature regime, which occurs when the limit $T\to0$ is taken at a positive chemical potential. The asymptotic expressions are found from the asymptotic solution of the matrix Riemann-Hilbert problem related to the determinant representation of the correlation functions.