Speaker
Description
The three-gluon vertex plays a central role in the infrared dynamics of Quan-
tum Chromodynamics (QCD). Gluon self-interaction shows the main diference
between this theory and others like quantum electrodynamics (QED), its non-
abelian nature. The appearance of a three-gluon vertex in the QCD Lagrangian
is intimately linked to both asymptotic freedom and con?nement in QCD. The
study of its non-perturbative features has attracted attention for the last decades
in both Dyson-Schwinger and lattice simulations. The three gluon vertex de-
pends on the incomimg momenta, q, r and p, with the kinematical constrain
q + r + p = 0. Most lattice studies focus in the symmetric (q2 = r2 = p2) and
soft-gluon (p = 0, and thus q2 = r2) cases where there is a single momentum
scale. Both kinematics exhibit an infrared zero-crossing which can be under-
stood as a consequence of the gluon-mass generation while the ghost remains
massless.
In this work, we present recent results for the three-gluon vertex from quenched
lattice-QCD in extended kinematics, i.e., beyond the limiting previously studied
cases. From our lattice results, two outstanding features of the non-perturbative
three-gluon vertex emerge:
the form-factor associated to the tree-level tensor is clearly dominant over
the others
the scalar form factors depend almost exclusively on the symmetric vari-
able s
Being its study of paramount theoretical relevance by itself, the three-gluon
vertex is also a central component in a variety of phenomenological studies in the
continuum. This ongoing search, based on the pro?table synergy between lat-
tice simulations and continuum methods, has a?orded a ?rmer grip on delicate
underlying patterns, establishing prominent connections with the emergence of
a mass-scale in the gauge sector of the theory.
Abstract
The three-gluon vertex plays a central role in the infrared dynamics of Quan-
tum Chromodynamics (QCD). Gluon self-interaction shows the main diference
between this theory and others like quantum electrodynamics (QED), its non-
abelian nature. The appearance of a three-gluon vertex in the QCD Lagrangian
is intimately linked to both asymptotic freedom and con?nement in QCD. The
study of its non-perturbative features has attracted attention for the last decades
in both Dyson-Schwinger and lattice simulations. The three gluon vertex de-
pends on the incomimg momenta, q, r and p, with the kinematical constrain
q + r + p = 0. Most lattice studies focus in the symmetric (q2 = r2 = p2) and
soft-gluon (p = 0, and thus q2 = r2) cases where there is a single momentum
scale. Both kinematics exhibit an infrared zero-crossing which can be under-
stood as a consequence of the gluon-mass generation while the ghost remains
massless.
In this work, we present recent results for the three-gluon vertex from quenched
lattice-QCD in extended kinematics, i.e., beyond the limiting previously studied
cases. From our lattice results, two outstanding features of the non-perturbative
three-gluon vertex emerge:
the form-factor associated to the tree-level tensor is clearly dominant over
the others
the scalar form factors depend almost exclusively on the symmetric vari-
able s
Being its study of paramount theoretical relevance by itself, the three-gluon
vertex is also a central component in a variety of phenomenological studies in the
continuum. This ongoing search, based on the pro?table synergy between lat-
tice simulations and continuum methods, has a?orded a ?rmer grip on delicate
underlying patterns, establishing prominent connections with the emergence of
a mass-scale in the gauge sector of the theory.
