Measurement of the static Stark Shift of the $7s{}^2{S}_{1\mathrm{/}2}$ level in atomic cesium

We report a new precision measurement of the dc Stark shift of the $6s{}^2{S}_{1\mathrm{/}2}\to 7s{}^2{S}_{1\mathrm{/}2}$ transition in atomic cesium-133. Our result is 0.72246 (29) $\text{Hz}(\text{V}\mathrm{/}\text{cm}{)}^{-2}$. This result differs from a previous measurement of the Stark shift by $\sim$0.5%. We use this value to recalculate the magnitude of the reduced dipole matrix elements $⟨7s\mathrm{\mid }\mathrm{\mid }r\mathrm{\mid }\mathrm{\mid }7p_j⟩$, as well as the vector transition polarizability for the $6s\to 7s$ transition, $\tilde{\beta }=27.043(36)a_0^3$. This determination helps resolve a critical discrepancy between two techniques for determining the vector polarizability.