Measurement of the Static Stark Shift of the 7s ^{2}S_{1/2} Level in Atomic Cesium.

We report a new precision measurement of the dc Stark shift of the 6s ^{2}S_{1/2}→7s ^{2}S_{1/2} transition in atomic cesium-133. Our result is 0.72246  (29)  Hz(V/cm)^{-2}. This result differs from a previous measurement of the Stark shift by ∼0.5%, or 4.7σ. We use this value to recalculate the magnitude of the reduced dipole matrix elements ⟨7s||r||7p_{j}⟩, as well as the vector transition polarizability for the 6s→7s transition, β[over ˜]=27.043 (36) a_{0}^{3}. This determination helps resolve a critical discrepancy between two techniques for determining the vector polarizability.