Structure functions and form factors close to the chiral limit from lattice QCD

Abstract

Results for nucleon matrix elements (arising from moments of structure functions) and form factors from a mixture of runs using Wilson, clover and overlap fermions (both quenched and unquenched) are presented and compared in an effort to explore the size of the chiral `regime', lattice spacing errors and quenching artefacts. While no run covers this whole range of effects the partial results indicate a picture of small lattice spacing errors, small quenching effects and only reaching the chiral regime at rather light quark masses.

7 pages, 7 figures; contribution to the 2003 Workshop on Lattice Hadron Physics, Cairns, Australia; error in Fig. 4 corrected; minor text changes