Multichannel quantum defect theory MQDT

D. Gauyacq I have a short comment on Prof. Schlag s remark on the multichannel quantum defect theory (MQDT) approach to ZEKE spectra The first ZEKE spectrum of NO was actually interpreted by using MQDT as early as 1987 [1]. In this work, a full calculation of the ZEKE peak intensities is carried out by the MQDT approach, which... 

Separation of the effects due to the long-range and short-range interactions greatly advances the understanding of the dynamics prevailing in continuum processes. Particularly useful general theoretical frameworks to this effect have been the R-matrix theory [44, 70] and the multichannel quantum defect theory (MQDT) [71, 72], They have been applied successfully to a wide variety of atomic and molecular systems, and the relevant material is too rich to be covered in this article. 

An alternative method to obtain the nonadiabatic wavefunctions [Eq. (4.1.1)], the coupled equation approach, will be discussed in Section 4.4.3. It has been used for an excited 1E+ state of H2 and the error is now smaller than 1 cm-1 for the lowest vibrational levels (Yu and Dressier, 1994). Multichannel Quantum Defect Theory (MQDT), discussed in Chapter 8, has also been used with success for the same problem by Ross and Jungen (1994). Finally, a variational numerical approach (Wolniewicz, 1996), gives very good results for H2. 

When a mechanism for each of the relevant decay channels is assumed and a set of specific interaction matrix elements is calculated by ab initio or semi-empirical methods, multichannel quantum defect theory (MQDT) (see Section 8.9) provides a basis for a unified and global treatment of the competing nonradiative decay processes and how these competing processes are sampled by specific experiments. Giusti-Suzor and Jungen (1984) were the first to apply MQDT to... 

Much effort has been invested to obtain a complete understanding of the detailed structure of Rydberg states of alkaline-earth atoms. In parallel to the experimental mapping of states went a successful parametrization of the observed spectra by the Multichannel Quantum Defect Theory (MQDT). The paper by Cooke presented at the last ICAP described the basic aspects of this approach. Specifically, the level structure was measured and analysed by MQDT for odd ... 

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