LAUSR

Investigation of quasibound states of black holes is significant for expected ultralight particles, as well as black holes through gravitational waves. We first investigate quasibound states of a massive scalar field for dilatonic charged black holes via numerical analysis. We study the complex eigenfrequencies of the massive scalar field in a wide range of gravitational fine structure constant $\ensuremath{\mu}M$ in detail, and show the effects of charge. Further, we study the eigenfrequencies of the massive field through an analytical approach by matching the near horizon solution and far field solution, and find its spectra for excited states by the iteration method. We demonstrate that the numerical solution and analytical solution perfectly agree with each other in the region where charge of the black hole is large, both for real and imaginary parts of the eigenfrequencies.