English

Pion Generalized Parton Distributions within a fully covariant constituent quark model

High Energy Physics - Phenomenology 2016-05-25 v2

Abstract

We extend the investigation of the Generalized Parton Distribution for a charged pion within a fully covariant constituent quark model, in two respects: (i) calculating the tensor distribution and (ii) adding the treatment of the evolution, needed for achieving a meaningful comparison with both the experimental parton distribution and the lattice evaluation of the so-called generalized form factors. Distinct features of our phenomenological covariant quark model are: (i) a 4D Ansatz for the pion Bethe-Salpeter amplitude, to be used in the Mandelstam formula for matrix elements of the relevant current operators, and (ii) only two parameters, namely a quark mass assumed to hold mq= 220m_q=~220 MeV and a free parameter fixed through the value of the pion decay constant. The possibility of increasing the dynamical content of our covariant constituent quark model is briefly discussed in the context of the Nakanishi integral representation of the Bethe-Salpeter amplitude.

Keywords

Cite

@article{arxiv.1603.04598,
  title  = {Pion Generalized Parton Distributions within a fully covariant constituent quark model},
  author = {C. Fanelli and E. Pace and G. Romanelli and G. Salme' and M. Salmistraro},
  journal= {arXiv preprint arXiv:1603.04598},
  year   = {2016}
}

Comments

Pages 20, figure 11 and table 8. Minor changes. To be published in EPJC