On the interplay between Coulomb and nuclear states in exotic atoms

The rearrangement of the Coulomb atomic spectrum in exotic atoms due to nuclear states bound by a real attractive short-range potential, and the coupling between atomic and nuclear states, was discussed and classified many years ago by Zeldovich. Here we generalize the discussion to physical situations for which a complex nuclear potential simulates the additional effects of nuclear absorption. As function of the strength parameter Wo of the imaginary part of the nuclear potential, then for W₀ ≳ W^crit₀ we find an almost complete relaxation of Zeldovich's phenomenon of rearrangement and Coulomb atomic states and nuclear states get decoupled from each other. The critical strength W^crit₀ is considerably weaker than the absorptivities encountered in exotic atoms experimentally observed. We briefly mention residual signatures of nuclear states in exotic atoms.