title: Chiral extrapolation of lattice moments of proton quark distributions.
abstract: We present the resolution of a long-standing discrepancy between the moments of parton distributions calculated from lattice QCD and their experimental values. We propose a simple extrapolation formula for the moments of the nonsinglet quark distribution u-d, as a function of quark mass, which embodies the general constraints imposed by the chiral symmetry of QCD. The inclusion of the leading nonanalytic behavior leads to an excellent description of both the lattice data and the experimental values of the moments.
authors.affiliation: Special Research Centre for the Subatomic Structure of Matter, and Department of Physics and Mathematical Physics, Adelaide University, Adelaide 5005 Australia.
authors.forename: W
authors.initials: W
authors.lastname: Detmold
authors.forename: W
authors.initials: W
authors.lastname: Melnitchouk
authors.forename: J W
authors.initials: JW
authors.lastname: Negele
authors.forename: D B
authors.initials: DB
authors.lastname: Renner
authors.forename: A W
authors.initials: AW
authors.lastname: Thomas