Symmetry, symmetry breaking, and pion parton distributions

Understand

Pion valence, glue and sea distributions are calculated using a continuum approach to the two valence-body bound-state problem.

• Since the framework is symmetry preserving, physical features of the distributions are properly expressed.
• The analysis reveals that the emergent phenomenon of dynamical chiral symmetry breaking causes a hardening of the valence-quark distribution function, ${q}^\pi(x)$.
• Nevertheless, this distribution exhibits the $x\simeq 1$ behaviour predicted by quantum chromodynamics (QCD).