arXiv:0808.1428·v2·High Energy Physics — Lattice
The electric dipole moment of the nucleon from simulations at imaginary vacuum angle theta
R. Horsley · T. Izubuchi · Y. Nakamura · D. Pleiter · P.E.L. Rakow · G. Schierholz · J. Zanotti
Abstract
We compute the electric dipole moment of proton and neutron from lattice QCD simulations with N_f=2 flavors of dynamical quarks at imaginary vacuum angle theta. The calculation proceeds via the CP odd form factor F_3. A novel feature of our calculation is that we use partially twisted boundary conditions to extract F_3 at zero momentum transfer. As a byproduct, we test the QCD vacuum at nonvanishing theta.
Comments: 22 pages, 10 figures