English

Poincar\'e-covariant analysis of heavy-quark baryons

Nuclear Theory 2018-06-20 v1 High Energy Physics - Phenomenology

Abstract

We use a symmetry-preserving truncation of meson and baryon bound-state equations in quantum field theory in order to develop a unified description of systems constituted from light- and heavy-quarks. In particular, we compute the spectrum and leptonic decay constants of ground-state pseudoscalar- and vector-mesons: qqˉq^\prime \bar q, QQˉQ^\prime \bar Q, with q,q=u,d,sq^\prime,q=u,d,s and Q,Q=c,bQ^\prime,Q = c,b; and the masses of JP=3/2+J^P=3/2^+ baryons and their first positive-parity excitations, including those containing one or more heavy quarks. This Poincar\'e-covariant analysis predicts that such baryons have a complicated angular momentum structure. For instance, the ground states are all primarily SS-wave in character, but each possesses PP-, DD- and FF-wave components, with the PP-wave fraction being large in the qqqqqq states; and the first positive-parity excitation in each channel has a large DD-wave component, which grows with increasing current-quark mass, but also exhibits features consistent with a radial excitation. The configuration space extent of all such baryons decreases as the mass of the valence-quark constituents increases.

Keywords

Cite

@article{arxiv.1801.09697,
  title  = {Poincar\'e-covariant analysis of heavy-quark baryons},
  author = {Si-Xue Qin and Craig D. Roberts and Sebastian M. Schmidt},
  journal= {arXiv preprint arXiv:1801.09697},
  year   = {2018}
}

Comments

12 pages, 5 figures, 4 tables