We study spectral properties of a non-Hermitian Hamiltonian describing a
quantum particle propagating in a random imaginary scalar potential. Cast in
the form of an effective field theory, we obtain an analytical expression for
the ensemble averaged one-particle Green function from which we obtain the
density of complex eigenvalues. Based on the connection between non-Hermitian
quantum mechanics and the statistical mechanics of polymer chains, we determine
the distribution function of a self-interacting polymer in dimensions d>4.Comment: 10 pages, 1 eps figur