  We are interested in finding the joint distribution function of the real and
imaginary parts of the local Green function for a system with chaotic internal
wave scattering and a uniform energy loss (absorption). For a microwave cavity
attached to a single-mode antenna the same quantity has a meaning of the
complex cavity impedance. Using the random matrix approach, we relate its
statistics to that of the reflection coefficient and scattering phase and
provide exact distributions for systems with beta=2 and beta=4 symmetry class.
In the case of beta=1 we provide an interpolation formula which incorporates
all known limiting cases and fits excellently available experimental data as
well as diverse numeric tests.
