Parametrisation of resonance structures in the multichannel quantum defect theory

Effect of Open Channels on the Isolation of Overlapping Resonances in the Uniformly Perturbed Rydberg Systems Studied by Multichannel Quantum Defect Theory

“…It begins from a factorization of the determinant of the physical scattering matrix S into background and resonance scattering 14,15 (4) where ν k is defined as with respect to the ionization threshold I k for the closed channel k; κ cc is a complex reactance matrix 16 defined in terms of the sub reactance matrix by . πμ denotes the phase shifts introduced by phase renormalization.…”

Optimization of generalized multichannel quantum defect reference functions for Feshbach resonance characterization

“…However, due to the asymmetric resonance profile, the comparison of width is not obvious. Actually, the resonance width can be directly extracted from the Y adia matrix, using a procedure proposed by Lecomte [15] point is to eliminate the open channels to build the block of the K matrix associated to the closed channel by applying Siegert aymptotic conditions, instead of doing the reverse as in eq.13 (we omitted the adia index for simplicity):…”

“…Following ref. [15], this goal is achieved in two steps. Two successive rotations of the initial adiabatic f c and g c (resp.…”

Study of the Resonance Structures of the Preionizing Spectrum of Molecular Hydrogen by Phase-shifted Multichannel Quantum Defect Theory

“…1 of the short-range reactance matrix K can be set to zero by phase renormalization. 5,26 With the tilde emphasizing phase shift, the phase-shifted reactance matrix is given as follows: (1) It is convenient to introduce a coupling parameter (i = 1, 2, 3) for the reactance matrix elements between the open and closed channels. Its square is related to the spectral width of the resonance peak of an autoionizing series i as =4Ryd /π , 2 where Ryd denotes the Rydberg constant and ν i denotes the effective quantum number defined by E = I i − Ryd/ for channel i.…”

“…[29]), where the complex reactance matrix denotes −i , first considered in Ref. [26]. Closed channels with higher ionization limits frequently act as interlopers, providing broad background peaks to the autoionizing series converging to the lowest ionization limit of the closed channels.…”