Excited hadrons and the analytical structure of bound-state interaction kernels

Abstract

We highlight Hermiticity issues in bound-state equations whose kernels are subject to a highly asymmetric mass and momentum distribution and whose eigenvalue spectrum becomes complex for radially excited states. We trace back the presence of imaginary components in the eigenvalues and wave functions to truncation artifacts and suggest how they can be eliminated in the case of charmed mesons. The solutions of the gap equation in the complex plane, which play a crucial role in the analytic structure of the Bethe-Salpeter kernel, are discussed for several interaction models and qualitatively and quantitatively compared to analytic continuations by means of complex-conjugate pole models fitted to real solutions.

Proceeding of the ECT* workshop "Nucleon Resonances From Photoproduction to High Photon Virtualities", talk given by B.E.; 8 pages, 2 figures with 6 graphs

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Cited by in corpus (21)

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• Off-shell persistence of composite pions and kaons
• Elucidating the effect of intermediate resonances in the quark interaction kernel on the time-like electromagnetic pion form factor
• Mass spectrum and decay constants of radially excited vector mesons
• Exploring the Quark-Gluon Vertex with Slavnov-Taylor Identities and Lattice Simulations
• Aspects of open-flavour mesons in a comprehensive DSBSE study
• Interplay of dynamical and explicit chiral symmetry breaking effects on a quark
• On the effect of resonances in the quark-photon vertex
• More about the light baryon spectrum
• The impact of transverse Slavnov-Taylor identities on dynamical chiral symmetry breaking
• Baryons and the Borromeo
• The time-like electromagnetic kaon form factor
• Parton distribution functions and transverse momentum dependence of heavy mesons
• The Podolsky propagator in gap and bound-state equations
• Timelike form factor for the anomalous process ${\gamma }^{\ast }\pi \to \pi \pi$
• A comprehensive approach to the physics of mesons
• Pseudo-scalar {\boldm $q\bar{q}$} bound states at finite temperatures within a Dyson-Schwinger--Bethe-Salpeter approach
• The Charm and Beauty of Strong Interactions