  We characterize the resonances of Stark Hamiltonians by the complex absorbing
potential method. Namely, we prove that the Stark resonances are the limit
points of complex eigenvalues of the Stark Hamiltonian with a quadratic complex
absorbing potential when the absorbing coefficient tends to zero. The proof
employs the complex distortion outside a cone introduced in the previous work
by the author. Potentials with local singularities such as the Coulomb
potential are allowed as perturbations.
