We study the neutron electric dipole moment in the presence of the CP-violating operators up to dimension five in terms of the QCD sum rules. It is found that the operator product expansion calculation is robust when exploiting a particular interpolating field for a neutron, while there exist some uncertainties on the phenomenological side. By using input parameters obtained from the lattice calculation, we derive a conservative limit for the contributions of the CP-violating operators. We also show the detail of the derivation of the sum rules.
|Original language||English (US)|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - Jun 26 2012|