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The electric dipole moment of the nucleon from simulations at imaginary vacuum angle theta

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 نشر من قبل Gerrit Schierholz
 تاريخ النشر 2008
  مجال البحث
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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.

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