QCD Corrections to Neutron Electric Dipole Moment from Dimension-six   Four-Quark Operators
  In this paper, the renormalization-group equations for the (flavor-conserving) CP-violating interaction are derived up to the dimension six, including all the four-quark operators, at one-loop level. We apply them to the models with the neutral scalar boson or the color-octet scalar boson which have CP-violating Yukawa interactions with quarks, and discuss the neutron electric dipole moment in these models. 
Junji Hisano, Koji Tsumura, Masaki J.S. Yang
hep-ph