  We describe a computational investigation of tunneling at finite energy in a
weakly coupled quantum mechanical system with two degrees of freedom. We
compare a full quantum mechanical analysis to the results obtained by making
use of a semiclassical technique developed in the context of instanton-like
transitions in quantum field theory. This latter technique is based on an
analytic continuation of the degrees of freedom into a complex phase space, and
the simultaneous analytic continuation of the equations of motion into the
complex time plane.
