%0 Journal Article
%T Pion Distribution Amplitude from Lattice QCD
%A V. M. Braun
%A S. Collins
%A M. G£¿ckeler
%A P. P¨¦rez-Rubio
%A A. Sch£¿fer
%A R. W. Schiel
%A A. Sternbeck
%J Physics
%D 2015
%I arXiv
%X We have calculated the second moment of the pion light-cone distribution amplitude using two flavors of dynamical (clover) fermions on lattices of different volumes, lattice spacings between $0.06 \, \mathrm {fm}$ and $0.08 \, \mathrm {fm}$ and pion masses down to $m_\pi\sim 150 \, \mathrm {MeV}$. Our result for the second Gegenbauer coefficient is $a_2 = 0.1364(154)(145)$ and for the width parameter $\langle \xi^2 \rangle = 0.2361(41)(39)$. Both numbers refer to the scale $\mu=2 \, \mathrm {GeV}$in the $\overline{\text{MS}}$ scheme, the first error is statistical including the uncertainty of the chiral extrapolation, and the second error is the estimated uncertainty coming from the nonperturbatively determined renormalization factors.
%U http://arxiv.org/abs/1510.07429v1