Resonances by the complex coordinate method with Hermitian Hamiltonian. IV. The linear correlation procedure

On the basis of the Hermitian representation of the complex coordinate method presented in paper I we suggest here a simple procedure to get a good estimate of both the position and width of a resonance for a given Hamiltonian. The complex energy E, which is associated with the resonance is obtained by solving the equation system λ1/‖E−Ē1‖=λ2/‖E−Ē2‖= λ3/‖E−Ē3‖, where {λn, n=1,2,3} are the lowest eigenvalues of a Hermitian Hamiltonian (Ĥθ−Ēn)*(Ĥθ−Ē n), Ĥθ is the complex rotated Hamiltonian, and Ē1,2,3 can be obtained, e.g., from conventional stabilization calculations where Im(Ē1,2,3)=0.