Author/Authors :
M. G?ckeler، نويسنده , , R. R. Horsley، نويسنده , , H. Perlt، نويسنده , , P.E.L. Rakow، نويسنده , , A. Sch?fer، نويسنده , , G. Schierholz، نويسنده , , A. Schiller، نويسنده ,
Abstract :
We calculate the non-forward quark matrix elements of operators with two covariant derivatives needed for the renormalisation of the second moment of generalised parton distributions in one-loop lattice perturbation theory using Wilson fermions. For some representations of the hypercubic group commonly used in simulations we determine the sets of all possible mixing operators. For those representations the one-loop mixing matrices of renormalisation factors are found. Due to non-vanishing contributions of operators with external ordinary derivatives the number of contributing operators increases compared to forward matrix elements.
Keywords :
Renormalisation , Lattice QCD , Generalised parton distributions , perturbation theory