Atomic parity violation (APV) experiments offer the opportunity to study the weak interactions at low-energy scales, providing valuable information about the Standard Model and nuclear physics. Owing to its high atomic mass, the strong mixing by the weak interaction of two opposite parity eigenstates, as well as the availability of many stable isotopes, ytterbium is a particularly good candidate for investigating APV effects. This brings within reach the possibility to detect the nuclear anapole moment of the Yb nucleus as well as to probe the variation of neutron skin among the different isotopes of this element.

Our group has recently succeeded in observing a large APV effect on Yb, in an experiment that concluded in 2009 at Berkeley with a measurement of the effect at the 10% level. With a new apparatus recently constructed in Mainz, we have improved our statistical sensitivity to a level that will allow us to perform measurements with a 0.1% accuracy, enough to probe the Yb anapole moment and neutron distributions.

References:

- D. R. Dounas-Frazer, K. Tsigutkin, A. Family, and D. Budker, Measurement of dynamic Stark polarizabilities by analyzing spectral lineshapes of forbidden transitions,
**Phys. Rev. A****82**(6), 062507 (2010) (**arXiv:1009.5952**) - K. Tsigutkin, D. Dounas-Frazer, A. Family, J. E. Stalnaker, V. V. Yashchuk, and D. Budker, Parity violation in atomic ytterbium: experimental sensitivity and systematics,
**Phys. Rev. A****81**(3), 032114 (2010) (**arXiv****:1001.0587**) - K. Tsigutkin, D. Dounas-Frazer, A. Family, J. E. Stalnaker, V. V. Yashchuk, D. Budker, Observation of a Large Atomic Parity Violation Effect in Ytterbium,
**Phys. Rev. Lett.****103**, 071601 (2009). (**arXiv:0906.3039**) - K. Tsigutkin, J. E. Stalnaker, D. Budker, S. J. Freedman, and V. V. Yashchuk, Towards measuring nuclear-spin-dependent and isotopic-chain atomic parity violation in Ytterbium, in From Parity Violation to Hadronic Structure and more…, Ed. by K. de Jager et al, Springer 2007. (
**physics/0608314**) - J. E. Stalnaker, D. Budker, S. J. Freedman, J. S. Guzman, S. M. Rochester, and V. V. Yashchuk, Dynamic Stark effect and forbidden-transition spectral lineshapes,
**Phys. Rev. A****73**, 043416 (2006). (**physics/0512111**) - J. E. Stalnaker, D. Budker, D. P. DeMille, S. J. Freedman, and V.V. Yashchuk, Experimental determination of the 6s
^{2 1}S_{0}->5d6s^{3}D_{1}magnetic-dipole transition amplitude in atomic ytterbium,**Phys. Rev. A****65**(2002), 031403. (**physics/0201026**) - D. Budker and J. E. Stalnaker, Magnetoelectric Jones dichroism in atoms
**Phys. Rev. Lett.,****91**(26), 263901 (2003). (**physics/0302096**) - D.F. Kimball, D. Clyde, D. Budker, D. DeMille, S.J. Freedman, S. Rochester, J.E. Stalnaker, and M. Zolotorev,
**Collisional Perturbation of States in Atomic Ytterbium by Helium and Neon**,**Phys. Rev. A****60**(2), 1103 (1999). - C.J. Bowers, D. Budker, D. DeMille, S.J. Freedman, G.Gwinner, and J.E. Stalnaker,
**Experimental investigation of the 6s**^{2 1}S_{0}**→****5d6s**^{3}**D**,_{1,2}forbidden transitions in atomic ytterbium**Phys. Rev. A****59**(5), 3513 (1999). - C.J. Bowers, D. Budker, E.D. Commins, D. DeMille, S.J. Freedman, A.-T. Nguyen, S.-Q. Shang, and M. Zolotorev,
**Experimental investigation of excited state lifetimes in atomic ytterbium**,**Phys. Rev. A****53**(5), 3103-9 (1996). - B. DeBoo, D. F. Kimball, C.-H. Li, and D. Budker,
**Multichannel Conical Emission and Parametric and Nonparametric Nonlinear Processes in Yb vapor**,**JOSA B**,**18**(5), 639-645 (2001). - D.F. Kimball,
**Parity-nonconserving optical rotation on the 6s6p**^{3}P_{0}**→****6s6p**^{1}P_{1}transition in atomic ytterbium**Phys. Rev. A****63**, 052113 (2001).