188 citations · 519 across the 8 of their papers we have counts for
4 papers · 2 filters
Light mesons in QCD and unquenching effects from the 3PI effective action
Richard Williams, Christian S. Fischer, Walter Heupel
We investigate the impact of unquenching effects on QCD Green's functions, in the form of quark-loop contributions to both the gluon propagator and three-gluon vertex, in a three-l…
The light scalar mesons as tetraquarks
Gernot Eichmann, Christian S. Fischer, Walter Heupel
We present a numerical solution of the four-quark Bethe-Salpeter equation for ground-state scalar tetraquarks with J^PC = 0^++. We find that the four-body equation dynamically gene…
Tetraquarks from the Bethe-Salpeter equation
Gernot Eichmann, Christian S. Fischer, Walter Heupel
We present a numerical solution of the four-quark Bethe-Salpeter equation for a scalar tetraquark. We find that the four-body equation dynamically generates pseudoscalar poles in t…
Four-point functions and the permutation group S4
Gernot Eichmann, Christian S. Fischer, Walter Heupel
Four-point functions are at the heart of many interesting physical processes. A prime example is the light-by-light scattering amplitude, which plays an important role in the calcu…