Abstract
We present a classical approximation for the peaks of survival resonances occurring when diffracting matter waves from absorption potentials. Generally, our simplified model describes the absorption-diffraction process around the Talbot time very well. Classical treatments of this process are presently lacking. For purely imaginary potentials, the classical model duplicates quantum-mechanical calculations. The classical model allows for simple evolution of phase-space probability densities, which in the limit of the effective Planck constant going to zero allows for a compact analytical expression of the survival probability as a function of remaining parameters. Our work extends the range of processes that can be described through classical analogs.