2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008

##### Quark-gluon vertex from $N_f = 2$ lattice QCD

**Authors**: Ayse Kızılersu, Orlando Oliveira, Paulo J. Silva, Jon-Ivar Skullerud, Andre Sternbeck

**Ref.**: Phys. Rev. D **103**, 114515 (2021)

**Abstract**: We study the quark–gluon vertex in the limit of vanishing gluon momentum using lattice QCD with 2 flavors of O(a) improved Wilson fermions, for several lattice spacings and quark masses. We find that all three form factors in this kinematics have a significant infrared strength, and that both the leading form factor λ1, multiplying the tree-level vertex structure, and the scalar, chiral symmetry breaking form factor λ3 are significantly enhanced in the infrared compared to the quenched (Nf = 0) case. These enhancements are orders of magnitude larger than predicted by one-loop perturbation theory. We find only a weak dependence on the lattice spacing and quark mass.