Measurement of Parity Nonconservation in Atomic Cesium

Abstract

A new measurement of parity nonconservation in cesium is reported. The experimental technique involves measurement of the 6S -* IS transition rate by use of crossed atomic and laser beams in a region of perpendicular electric and magnetic fields. Our results are Imgf PNc/i8 = -1.65 ± 0.13 mV/cm and Cip = -2 ± 2. These results are in agreement with previous measurements in cesium and the predictions of the electroweak standard model. This experimental technique will allow future measurements of significantly higher precision.

Atomic parity violation measurements in the highly forbidden 6S 1/2 - 7S1/2 caesium transition. - III. Data acquisition and processing. Results and implications

“…Because all photons are emitted in the direction and at the frequency of the probe, high efficiency is expected. Different experimental approaches are currently being investigated by the Zurich [26] and Boulder [6] groups. Results from independent groups will again provide valuable cross-checks.…”

Measurement of the forbidden 6S - 8S M1 transition in caesium with an electric field

“…Yet, a clear parity violation in quantitative agreement with the theoretical predictions has already been observed in the 6S -7S transition in our group [2,3], then confirmed by other authors [4]. In view of the unusually long integration times in our 6S -7S measurements (5 h for S/N = 1), our first priority is to improve the technique.…”

“…This value is consistent with the theoretical calculations of reference [8] (see above formula (2)). 4 We obtain finally : and using equation (9) : or, combining the uncertainties quadratically :…”

“…It is now well established since three experiments on the 6S -7S transition of caesium have been successfully performed [2][3][4].…”

“…The reason is that obtaining several consistent values of the same atomic quantity in different experimental conditions and through observation of different physical quantities will crucially reduce the possibility that significant sources of systematics may have been overlooked Furthermore such studies provide new tests of the validity of the atomic calculations used in the prediction of the parity violation effect. This is why our group as well as others [4,5] proceed further in studying these transitions.…”