Instanton traces in lattice gluon correlation functions

Ph. Boucaud (1) , F. de Soto (2) , A. Le Yaouanc (1) , J. P. Leroy (1) , J. Micheli (1) , O. Pene (1) , J. Rodriguez-Quintero

1 LPT - Laboratoire de Physique Théorique d'Orsay [Orsay]
2 LPSC - Laboratoire de Physique Subatomique et de Cosmologie

Strong coupling constant computed in Landau gauge and MOM renormalization scheme from lattice two and three gluon Green Functions exhibits an unexpected behavior in the deep IR, showing a maximum value around $1 {\rm GeV}$. We analise this coupling below this maximum within a semiclassical approach, were gluon degrees of freedom at very low energies are described in terms of the classical solutions of the lagrangian, namely instantons. We provide some new results concerning the relationship between instantons and the low energy dynamics of QCD, by analising gluon two- and three-point Green functions separately and with the help of a cooling procedure to eliminate short range correlations.

Domaines: Physique des Hautes Energies - Phénoménologie [hep-ph]

Ph. Boucaud, F. de Soto, A. Le Yaouanc, J. P. Leroy, J. Micheli, et al.. Instanton traces in lattice gluon correlation functions. XXXXth Rencontres de Moriond - QCD and Hadronic interactions at high energy, Mar 2005, La Thuile, France. ⟨hal-00008512⟩