We analyze the CP-violating electric dipole form factor of the nucleon in the framework of covariant baryon chiral perturbation theory. We give a new upper bound on the vacuum angle, |\theta_0| \lesssim 2.5 \cdot 10^{-10}. The quark mass dependence of the electric dipole moment is discussed and compared to lattice QCD data. We also perform the matching between its representations in the three- and two-flavor theories.
@article{arxiv.0911.3981,
title = {New insights into the neutron electric dipole moment},
author = {K. Ottnad and B. Kubis and U. -G. Meißner and F. -K. Guo},
journal= {arXiv preprint arXiv:0911.3981},
year = {2010}
}
Comments
9 pages, 3 figures, version published in Phys. Lett. B