Using recent high-precision measurements of electric dipole matrix elements of atomic cesium, we make an improved determination of the scalar (α) and vector (β) polarizabilities of the cesium 6s 2 S 1/2 → 7s 2 S 1/2 transition calculated through a sum-over-states method. We report values of α = −268.82 (30) a 3 0 and β = 27.139 (42) a 3 0 with the highest precision to date. We find a discrepancy between our value of β and the past preferred value, resulting in a significant shift in the value of the weak charge Qw of the cesium nucleus. Future work to resolve the differences in the polarizability will be critical for interpretation of parity non-conservation measurements in cesium, which have implications for physics beyond the Standard Model.

No abstract

We report a measurement of the ratio of electric dipole transition matrix elements of cesium for the 6p 2 P 1/2 → 7s 2 S 1/2 and 6p 2 P 3/2 → 7s 2 S 1/2 transitions. We determine this ratio of matrix elements through comparisons of two-color, two-photon excitation rates of the 7s 2 S 1/2 state using laser beams with polarizations parallel to one another vs. perpendicular to one another. Our result of R ≡ 7s 2 S 1/2 ||r||6p 2 P 3/2 / 7s 2 S 1/2 ||r||6p 2 P 1/2 = 1.5272 (17) is in excellent agreement with a theoretical prediction of R = 1.5270 (27). Moreover, the accuracy of the experimental ratio is sufficiently high to differentiate between various theoretical approaches. To our knowledge, there are no prior experimental measurements of R. Combined with our recent determination of the lifetime of the 7s 2 S 1/2 state, we determine reduced matrix elements for these two transitions, 7s 2 S 1/2 ||r||6p 2 P 3/2 = −6.489 (5) a0 and 7s 2 S 1/2 ||r||6p 2 P 1/2 = −4.249 (4) a0. These matrix elements are also in excellent agreement with theoretical calculations. These measurements improve knowledge of Cs properties needed for parity violation studies and provide benchmarks for tests of high-precision theory.

No abstract

Precision measurements of parity non-conserving (PNC) interactions in atoms, molecules and ions can lead to the discovery of new physics beyond the standard model and understanding of weakforce induced interactions in the nucleus. In this paper, we propose and analyze a novel atomic parity violation measurement scheme for a forbidden transition where we combine a two-pathway coherent control mechanism with probe gain techniques. We detail a feasible experimental geometry for 6S 1/2 → 7S 1/2 transitions in a cesium vapor cell, and consider the statistical noise of such a measurement under reasonable laboratory conditions. We estimate the signal-to-noise ratio to be approaching ∼ 2.3/ √ Hz. This scheme, with low expected systematic errors, would allow for precise measurements in cesium and other heavy metal systems.