Pion valence quark distribution from matrix element calculated in lattice QCD

Raza Sabbir Sufian, Joseph Karpie, Colin Egerer, Kostas Orginos, Jian-Wei Qiu, David G. Richards
2019 Physical Review D  
We present the first exploratory lattice QCD calculation of the pion valence quark distribution extracted from spatially separated current-current correlations in coordinate space. We show that an antisymmetric combination of vector and axial-vector currents provides direct information on the pion valence quark distribution. Using the collinear factorization approach, we calculate the perturbative tree-level kernel for this current combination and extract the pion valence distribution. The main
more » ... goal of this article is to demonstrate the efficacy of this general lattice QCD approach in the reliable extraction of parton distributions. With controllable power corrections and a good understanding of the lattice systematics, this method has the potential to serve as a complementary to the many efforts to extract parton distributions in global analyses from experimentally measured cross sections. We perform our calculation on an ensemble of 2+1 flavor QCD using the isotropic-clover fermion action, with lattice dimensions 32^3× 96 at a lattice spacing a=0.127 fm and the quark mass equivalent to a pion mass m_π≃ 416 MeV.
doi:10.1103/physrevd.99.074507 fatcat:enbp6asllbgybcviruszd5eymy