Year: 2016
Type: article
Abstract: A symmetry-preserving truncation of the two-body bound state problem in relativistic quantum field theory is used to compute the leading-twist parton distribution amplitudes (PDAs) for the first radial excitations of the $\ensuremath{\pi}$ and $K$ mesons. In common with ground states in these channels, the PDAs are found to be dilated with respect to the relevant conformal-limit form and skewed toward the heavier valence quark in asymmetric systems. In addition, the PDAs of radially excited pseudoscalar mesons are not positive definite, owing to the fact that dynamical chiral symmetry breaking (DCSB) forces the leptonic decay constant of such states to vanish in the chiral limit. These results highlight that DCSB is expressed visibly in every pseudoscalar meson constituted from light quarks. Hence, so long as its impact is empirically evident in the pseudoscalar members of a given spectrum level, it is unlikely that chiral symmetry is restored in any of the hadrons that populate this level.
Institutions: Nanjing University, Nankai University, Peking University, Collaborative Innovation Center of Quantum Matter, State Key Laboratory of Nuclear Physics and Technology, Argonne National Laboratory, Forschungszentrum Jülich, Jülich Aachen Research Alliance, Chinese Academy of Sciences, Institute of Theoretical Physics
Language: Latvian
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2344318134