Distribution amplitudes of light-quark mesons from lattice QCD

• Published in: Physics letters. B Vol. 731; pp. 13 - 18
• Main Authors: Segovia, Jorge, Chang, Lei, Cloët, Ian C., Roberts, Craig D., Schmidt, Sebastian M., Zong, Hong-shi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 04-04-2014
• Subjects: Amplitudes; Broken symmetry; Dynamical chiral symmetry breaking; Dyson–Schwinger equations; Lattice-regularised QCD; Lattices; Light mesons; Light-front quantum field theory; Mathematical models; Mesons; Parton distribution amplitudes; Partons; Quantum chromodynamics; Strange quarks; Vector mesons; Strange quarks; Dynamical chiral symmetry breaking; Lattice-regularised QCD; Parton distribution amplitudes; Light-front quantum field theory; Light mesons; Dyson–Schwinger equations; Quantum chromodynamics
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2014.02.006

We exploit a method introduced recently to determine parton distribution amplitudes (PDAs) from minimal information in order to obtain light-quark pseudoscalar and vector meson PDAs from the limited number of moments produced by numerical simulations of lattice-regularised QCD. Within errors, the PDAs of pseudoscalar and vector mesons constituted from the same valence quarks are identical; they are concave functions, whose dilation expresses the strength of dynamical chiral symmetry breaking; and SU(3)-flavour symmetry is broken nonperturbatively at the level of 10%. Notably, the appearance of precision in the lattice moments is misleading. The moments also exhibit material dependence on lattice volume, especially for the pion. Improvements need therefore be made before an accurate, unified picture of the light-front structure of light-quark pseudoscalar and vector mesons is revealed.