ar X iv : h ep - l at / 0 41 10 28 v 1 2 0 N ov 2 00 4 Lattice Computations of the Pion Form Factor

The pion electromagnetic form factor is often considered a good observable for studying the onset, with increasing energy, of the perturbative QCD regime for exclusive processes. It is believed that, because the pion is the lightest and simplest hadron, a perturbative description will be valid at lower energy scales than predictions for heavier and more complicated hadrons such as the nucleon [1]. A pseudoscalar particle has only a single electromagnetic form factor, F (Q), where Q is the four-momentum transfer, and furthermore atQ = 0, this form factor is normalized to the electric charge of the particle, F (Q = 0) = 1; the magnetic form factor vanishes. Thus in this paper, we will be measuring the form factor of the positively charged π. The experimentally observed behavior of the form factor at small momentum transfer is well described by the vector meson dominance (VMD) hypothesis [2, 3, 4]