Hyperfine structure evolution in an electric field and determination of tensor polarizabilities in He (4 and 5 1D)

Abstract
Variations of hyperfine structure in 3He (n 1D) are calculated as a function of an applied electric field. Using a quantum beat method on a fast helium beam excited and aligned by a thin carbon foil, we observe the time evolution of the alignment for a set of static electric fields. Tensor polarizabilities of levels are deduced