Precision determination of electroweak coupling from atomic parity violation and implications for particle physics
Abstract
We carry out high-precision calculation of parity violation in cesium atom, reducing theoretical uncertainty by a factor of two compared to previous evaluations. We combine previous measurements with our calculations and extract the weak charge of the 133Cs nucleus, Q_W = -73.16(29)_exp(20)_th. The result is in agreement with the Standard Model (SM) of elementary particles. This is the most accurate to-date test of the low-energy electroweak sector of the SM. In combination with the results of high-energy collider experiments, we confirm the energy-dependence (or "running") of the electroweak force over an energy range spanning four orders of magnitude (from ~10 MeV to ~100 GeV). Additionally, our result places constraints on a variety of new physics scenarios beyond the SM. In particular, we increase the lower limit on the masses of extra -bosons predicted by models of grand unification and string theories.
Keywords
Cite
@article{arxiv.0902.0335,
title = {Precision determination of electroweak coupling from atomic parity violation and implications for particle physics},
author = {S. G. Porsev and K. Beloy and A. Derevianko},
journal= {arXiv preprint arXiv:0902.0335},
year = {2010}
}
Comments
4 pages/3 figs /1 table