English

The quark gap equation in light-cone gauge

High Energy Physics - Phenomenology 2025-10-21 v2 Nuclear Theory

Abstract

We calculate the quark self-energy correction in light-cone gauge motivated by distribution amplitudes whose definition implies a Wilson line. The latter serves to preserve the gauge invariance of the hadronic amplitudes and becomes trivial in light-cone gauge. Therefore, the calculation of the distribution amplitudes simplifies significantly provided that wave functions and propagators are obtained in that gauge. In here, we explore the corresponding Dyson-Schwinger equation in its leading truncation and with a dressed vertex derived from a Ward identity in light-cone gauge. The quark's mass and wave renormalization functions, as well as a third complex-valued amplitude, are found to depend on the relative orientation of the quark momentum and a light-like four-vector, which expresses a geometric gauge dependence of the propagator.

Keywords

Cite

@article{arxiv.2411.00106,
  title  = {The quark gap equation in light-cone gauge},
  author = {Roberto Correa da Silveira and Fernando E. Serna and Bruno El-Bennich},
  journal= {arXiv preprint arXiv:2411.00106},
  year   = {2025}
}

Comments

Accepted for publication in PRD. An improved numerical treatment of divergences that occur in the C functions and use of the Cornwall gluon propagator derived in pinch technique lead to revised numerical results. In particular, the C functions in Figs. 3 and 6 are very small or consistent with zero depending on the frame of the quark. The conclusions are barely modified