Origin of the infrared enhancement of the quark wave-function renormalization Z(p)

Determine whether the observed infrared enhancement of the lattice quark wave-function renormalization Z(p) at zero temperature and chemical potential in SU(2) with unimproved Wilson fermions on coarse lattices is an intrinsic feature of two-colour QCD or a lattice artifact arising from the fermion action and coarse lattice spacing.

Background

The paper finds that Z(p) is enhanced in the infrared, in contrast to prior SU(3) lattice calculations with various fermion formulations where Z(p) is typically suppressed. This discrepancy could reflect genuine differences between two-colour QCD and real QCD, or it could be due to discretization artifacts from using unimproved Wilson fermions on relatively coarse lattices.

Clarifying the source of this behavior requires additional simulations, ideally on finer lattices, to separate physical effects from lattice artifacts.