Details

Autor(en) / Beteiligte

• Cui, Z.-F.
• Zhang, J.-L.
• Binosi, D.
• De Soto, F.
• Mezrag, C.
• Papavassiliou, J.
• Roberts, C. D.
• Rodríguez-Quintero, J.
• Segovia, J.
• Zafeiropoulos, S.

Titel

Effective charge from lattice QCD

Ist Teil von

• Chinese physics C, 2020-08, Vol.44 (8), p.83102

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Abstract Using lattice configurations for quantum ​​​​​chromodynamics (QCD) generated with three domain-wall fermions at a physical pion mass, we obtain a parameter-free prediction of QCD’s renormalisation-group-invariant process-independent effective charge, . Owing to the dynamical breaking of scale invariance, evident in the emergence of a gluon mass-scale, GeV, this coupling saturates at infrared momenta: . Amongst other things: is almost identical to the process-dependent (PD) effective charge defined via the Bjorken sum rule; and also that PD charge which, employed in the one-loop evolution equations, delivers agreement between pion parton distribution functions computed at the hadronic scale and experiment. The diversity of unifying roles played by suggests that it is a strong candidate for that object which represents the interaction strength in QCD at any given momentum scale; and its properties support a conclusion that QCD is a mathematically well-defined quantum field theory in four dimensions.