Rydberg orbitals definition

Both definitions are natural since wq turns out to be the ratio of the microwave frequency w and the Kepler firequency H of the Rydberg electron, and Sq is the ratio of the microwave field strength and the field strength experienced by an electron in the noth Bohr orbit of the hydrogen atom. Motivated by the above discussion we have redrawn the results obtained by Bayfield and Koch (1974) and present them in Fig. 7.2 as an ionization signal (in arbitrary units) versus the scaled field strength defined in (7.1.3). For no in (7.1.3) we chose no = 66, the centroid of the band of Rydberg states present in the atomic beam. 

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