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arXiv · 1803.00519

Heavy and heavy-light mesons in the Covariant Spectator Theory

Abstract

The masses and vertex functions of heavy and heavy-light mesons, described as quark-antiquark bound states, are calculated with the Covariant Spectator Theory (CST). We use a kernel with an adjustable mixture of Lorentz scalar, pseudoscalar, and vector linear confining interaction, together with a one-gluon-exchange kernel. A series of fits to the heavy and heavy-light meson spectrum were calculated, and we discuss what conclusions can be drawn from it, especially about the Lorentz structure of the kernel. We also apply the Brodsky-Huang-Lepage prescription to express the CST wave functions for heavy quarkonia in terms of light-front variables. They agree remarkably well with light-front wave functions obtained in the Hamiltonian basis light-front quantization (BLFQ) approach, even in excited states.

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Alfred Stadler, Sofia Leitão, M. T. Peña, Elmar P. Biernat. 2018-03-01. Heavy and heavy-light mesons in the Covariant Spectator Theory. https://doi.org/10.1007/s00601-018-1355-1

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