Inverted hyperfine structure

In Chap. 7 we have discussed how hyperfine structure can be determined by level-crossing spectroscopy. Clearly, alkali atom states can readily be studied using this technique after step-wise excitation. We will here instead choose an example illustrating fine-structure measurements. In Fig.9.17 the example of the inverted sodium 4d 05/2,3/2 given. 

In Fig. 2.16 hyperfine structures for two cases are displayed, one for the case of a positive a value normaF structure) and one for the case of a negative a value inverted structure). Clearly, both signs can occui, since the sign of the gi factor varies for different nuclei. (The sign of k can also vaxy.)... 

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