Abstract
We discuss results of the most accurate to-date test of the low-energy electroweak sector of the standard model of elementary particles. Combining previous measurements with our high-precision calculations we extracted the weak charge of the nucleus, [S. G. Porsev, K. Beloy, and A. Derevianko, Phys. Rev. Lett. 102, 181601 (2009)]. The result is in perfect agreement with predicted by the standard model, , and confirms energy dependence (or running) of the electroweak interaction and places constraints on a variety of new physics scenarios beyond the standard model. In particular, we increase the lower limit on the masses of extra -bosons predicted by models of grand unification and string theories. This paper provides additional details to the earlier paper. We discuss large-scale calculations in the framework of the coupled-cluster method, including full treatment of single, double, and valence triple excitations. To determine the accuracy of the calculations we computed energies, electric-dipole amplitudes, and hyperfine-structure constants. An extensive comparison with high-accuracy experimental data was carried out.
- Received 21 June 2010
DOI:https://doi.org/10.1103/PhysRevD.82.036008
© 2010 The American Physical Society