Ponente
Descripción
Phenomenological evidence indicates that low-excitation hadrons often decay via the $^3P_0$ mechanism, involving the creation of a light quark-antiquark pair with zero angular momentum. This scalar decay term arises spontaneously upon chiral symmetry breaking, despite Quantum Chromodynamics being mediated by spin-one gluons and displaying chiral symmetry in its Lagrangian. We explore this by employing the non-perturbative quark-gluon vertex in the Landau gauge, alongside a constant chromoelectric field background similar to the Schwinger pair production in Quantum Electrodynamics. Our results support the $^3P_0$ mechanism at momenta below the fermion mass scale, though ultrarelativistic fermions mostly exhibit $^3S_1$ quantum numbers. In QED, $^3S_0$ dominates, while in QCD, $^3P_0$ is favored at sub-GeV momenta due to the requirement of color singlet formation.
