High precision atomic parity nonconservation measurement using a spin polarized cesium beam and the nuclear anapole moment of Cesium-133

A 0.35% measurement of parity nonconservation (PNC) using the {dollar}6Sto 7S{dollar} transition in atomic cesium has been performed. This result represents the most accurate measurement of atomic PNC to date and, in conjunction with highly accurate atomic structure calculations, provides a unique, high precision test of the Standard model of electoweak unification. Also, by measuring the PNC on two different hyperfine components for the 6S-7S transition, a new manifestation of PNC in atomic nuclei has been observed and measured--the nuclear anapole moment. Finally, we have made an improved measurement (0.1% uncertainty) of the ratio {dollar}alpha/beta{dollar} for the 6S-7S transition, which is important for the interpretation of the PNC measurement.; The new PNC experiment used a spin polarized cesium beam, a new detection scheme, and an improved power-enhancing optical interferometer. A shot noise limited PNC signal-to-noise ratio 7 times larger than the previous measurement was achieved. Two frequency-stabilized diode lasers were used to optically pump the atomic beam, a third was used for detection, and a fourth was used to probe the spin polarization. Extensive testing of the apparatus for potential systematic effects was performed, and many previously unknown errors were discovered. Control of the potential systematic errors required development of many new optical and mechanical systems.