Preliminaries on a lattice analysis of the pion light-cone wave function: A partonic signal? art. no. 074511

We present the first attempt of new method to compute the pion li.-ht-cone wave function (LCWF) on the lattice. We compute the matrix element between the pion and the vacuum of a nonlocal operator: the propagator of a "scalar quark" (named, for short a "squark"). A theoretical analysis shows that fo r some kinematical conditions (an energetic pion and hard squark) this matr ix element depends dominantly on the LCWF Phi (pi)(u),u is an element of [0 ,1]. On the lattice, the discretization of the par-ton momenta imposes furt her constraints on the pion momentum. The two-point Green functions made of squark-quark and squark-squark fields show a hadronlike bound-state behavi or and verify the standard energy spectrum. We show some indications that d uring a short time, after being created, the system of the spectator quark and the squark behave like partons, before they form a hadronlike bound sta te. This short time is the place where the partonic wave function has to be looked for.