J an 2 01 9 Measurement of the Stark shift of the 6 s 2 S 1 / 2 → 7 p 2 P J transitions in atomic cesium

We report measurements of the Stark shift of the cesium 6s 2S3/2 → 7p 2P3/2 and the 6s 2S1/2 → 7p 2P1/2 transitions at λ = 456 nm and 459 nm, respectively, in an atomic beam. From these, we determine the static scalar polarizability for both 7P states, and the tensor polarizability for the 7P3/2 state. The fractional uncertainty of the scalar polarizabilites is ∼0.18%, while that of the tensor term is 0.66%. These measurements provide sensitive tests of theoretical models of the Cs atom, which has played a central role in parity nonconservation measurements.