Asymptotics of the Spectrum of a Threedimensional Hartree Type Operator Near Upper Boundaries of Spectral Clusters
摘要
We consider the eigenproblem for a Hartree type operator with a small parameter at nonlineratiry, where the self-action potential is the difference between the Coulomb potential and the screened Coulomb potential. We find asymptotic eigenvalues and asymptotic eigenfunctions near the upper boundaries of spectral clusters which appear near the energy levels of an unperturbed operator.