• DOI:10.1103/PhysRevD.92.034505
• Corpus ID: 118695550

The chromomagnetic operator on the lattice

@inproceedings{Constantinou2014TheCO,
  title={The chromomagnetic operator on the lattice},
  author={Martha Constantinou and M. Leineker Costa and R. Frezzotti and V. Lubicz and Guido Martinelli and Davide Meloni and Haris Panagopoulos and Silvano Simula},
  year={2014}
}

• M. Constantinou, M. Costa, +5 authors S. Simula
• Published 20 November 2013
• Physics

We study matrix elements of the “chromomagnetic” operator on the lattice. This operator is contained in the strangeness-changing effective Hamiltonian which describes electroweak effects in the Standard Model and beyond. Having dimension 5, the chromomagnetic operator is characterized by a rich pattern of mixing with other operators of equal and lower dimensionality, including also non gauge invariant quantities; it is thus quite a challenge to extract from lattice s imulations a clear signal for the hadronic matrix elements of this operator. We compute all relevant mixing coefficients to one loop in lat tice perturbation theory; this necessitates calculating both 2-point (quark-antiquark) and 3- point (gluon-quark-antiquark) Green’s functions at nonzero quark masses. We use the twisted mass lattice formulation, with Symanzik improved gluon action. For a comprehensive presentation of our results, along with detailed explanations and a more complete list of references, we refer to our forthcoming publication [1].