Vacuum expectation value of A^2 from LQCD
  We argue from LQCD that there is a non vanishing v.e.v of $A_a^\mu A^a_\mu$ in QCD in the Landau gauge. We use operator product expansion to provide a clear definition of $A_a^\mu A^a_\mu$ and extract a number both in the quenched and unquenched case. 
O. P\`ene, B. Blossier, Ph. Boucaud, A. Le Yaouanc, J.P. Leroy, J.   Micheli, M.Brinet, M. Gravina, F. De Soto, Z. Liu, V. M...
hep-lat