We study charmed and strange baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channel 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 produces resonances with negative parity from s-wave interaction of pseudoscalar and vector mesons with 1/2 + and 3/2 + baryons. Resonances in all the isospin, spin, and strange sectors with one, two, and three charm units are studied. Our results are compared with experimental data from several facilities, such as the CLEO, Belle or BaBar Collaborations, as well as with other theoretical models. Some of our dynamically generated states can be readily assigned to resonances found experimentally, while others do not have a straightforward identification and require the compilation of more data and also a refinement of the model. In particular, we identify the Ξc(2790) and Ξc(2815) resonances as possible candidates for a heavy-quark spin symmetry doublet.

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We study charmed baryon resonances which are generated dynamically within a unitary mesonbaryon coupled channel model that treats the heavy pseudoscalar and vector mesons on equal footing as required by heavy-quark symmetry. It is an extension of recent SU(4) models with tchannel vector meson exchanges to an SU(8) spin-flavor scheme, but differs considerably from the SU(4) approach in how the strong breaking of the flavor symmetry is implemented. Some of our dynamically generated states can be readily assigned to recently observed baryon resonances, while others do not have a straightforward identification and require the compilation of more data as well as an extension of the model to d-wave meson-baryon interactions and p-wave coupling in the neglected s-and u-channel diagrams. Of several novelties, we find that the Λc(2595), which emerged as a N D quasi-bound state within the SU(4) approaches, becomes predominantly a N D * quasi-bound state in the present SU(8) scheme.

The anti-D meson self-energy is evaluated self-consistently, using unitarized coupledchannel theory, by computing the in-medium meson-baryon T -matrix in the C = −1, S = 0 sector. The heavy pseudo-scalar and heavy vector mesons,D andD * , are treated on equal footing as required by heavy quark spin symmetry. Results for energy levels and widths of D − mesic atoms in 12 C, 40 Ca, 118 Sn and 208 Pb are presented. The spectrum contains states of atomic and of nuclear types for all nuclei.D 0 -nucleus bound states are also obtained. We find that, after electromagnetic and nuclear cascade, these systems end up with theD bound in the nucleus, either as a meson or as part of a exoticDN (pentaquark) loosely bound state.

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