Absorption Spectrum of Atomic Lithium in High Magnetic Fields

Quasi-Landau resonances have been recorded for lithium atoms in magnetic fields of up to 47 kG, with a spacing of only half the cyclotron frequency rather than $\frac{3}{2}$ as expected from previous theory. The intensity distribution over satellites in the $l$-mixing region (including the appearance of parity-forbidden transitions) is discussed in terms of magnetic mixing among nearly degenerate levels. An intensity sum rule is demonstrated.