Brömmel, D.FZJ* ; Göckeler, M. ; Diehl, M. ; Hägler, P. ; Horsley, R. ; Pleiter, D.FZJ* ; Rakow, P. E. L. ; Schäfer, A. ; Schierholz, G. ; Zanotti, J. M.

2006

Report No.: DESY 05-169; Edinburgh 2005/10

Abstract: Moments of generalised parton distributions can be related to off-forward matrix elements of local operators. We calculate a few of the leading twist matrix elements for the pion on the lattice. The simulations are performed using two flavours of dynamical fermions and a range of pion masses from 550 to 1090 MeV. Our lattice spacings and spatial volumes lie in the range 0.07-0.12 fm and (1.6-2.2 fm)^3, respectively. Key features of our investigation are the use of O(a) improved Wilson fermions and non-perturbative renormalisation. We present first results for the two lowest moments of the generalised parton distributions of the pion and compare the pion electromagnetic form factor F_pi to experimental data. Good agreement is found between lattice data and experiment.

1. 899 - ohne Topic (POF3-899) (POF3-899)