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arXiv · 1212.3943

Heavy-quark spin symmetry for charmed and strange baryon resonances

Abstract

We study charmed and strange baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channels model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa chiral Lagrangian to SU(8) spin-flavor symmetry plus a suitable symmetry breaking. The model generates resonances with negative parity from the s-wave interaction of pseudoscalar and vector mesons with 1/2+ and 3/2+ baryons in all the isospin, spin, and strange sectors with one, two, and three charm units. Some of our results can be identified with experimental data from several facilities, such as the CLEO, Belle, or BaBar Collaborations, as well as with other theoretical models, whereas others do not have a straightforward identification and require the compilation of more data and also a refinement of the model.

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Olena Romanets, Laura Tolos, Carmen Garcia-Recio, Juan Nieves, Lorenzo Luis Salcedo, Rob Timmermans. 2012-12-17. Heavy-quark spin symmetry for charmed and strange baryon resonances. https://doi.org/10.1016/j.nuclphysa.2013.01.033

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