163 research outputs found
excited states within a HQSS model
We have reviewed the renormalization procedure used in the unitarized
coupled-channel model of Phys. Rev. D85 114032 (2012), and its impact in the
, , and sector, where five states have been
recently observed by the LHCb Collaboration. The meson-baryon interactions used
in the model are consistent with both chiral and heavy-quark spin symmetries
and lead to a successful description of the observed lowest-lying odd parity
resonances and , and and
resonances. We show that some (probably at least three) of
the states observed by LHCb will also have odd parity and spins and
, belonging two of them to the same HQSS multiplets that the latter strangenessless
heavy baryons.Comment: 11 pages, 3 figures, 6 tables, published in The European Physical
Journal
Coupled channels dynamics in the generation of the resonance
We look into the newly observed state from the molecular
perspective in which the resonance is generated from the , and channels. We find that this picture provides a
natural explanation of the properties of the state. We stress
that the molecular nature of the resonance is revealed with a large coupling of
the to the channel, that can be observed in the
decay which is incorporated
automatically in our chiral unitary approach via the use of the spectral
function of in the evaluation of the loop function.Comment: 11 pages, 8 figure
and excited states within a HQSS model
We study odd parity and resonances using a unitarized
coupled-channel framework based on a HQSS-extended
Weinberg-Tomozawa baryon-meson interaction, while paying a special attention to
the renormalization procedure. We predict a large molecular
component for the with a dominant light-degree-of-freedom
spin configuration. We discuss the differences between the
and states, and conclude that they cannot be
SU(3) siblings, whereas we predict the existence of other states, two
of them related to the two-pole structure of the . It is of
particular interest a pair of and poles, which form a HQSS
doublet and that we tentatively assign to the and ,
respectively. Within this picture, the would be part of a SU(3)
sextet, containing either the or the , and
that would be completed by the . Moreover, we identify a
sextet with the state and the recently discovered
. Assuming the equal spacing rule and to complete this
multiplet, we predict the existence of a odd parity state,
with a mass of 6360 MeV and that should be seen in the channel.Comment: 13 pages, 5 figures, 4 table
Description of the and states as molecular states
In this work we study several and states dynamically
generated from the meson-baryon interaction in coupled channels, using an
extension of the local hidden gauge approach in the Bethe-Salpeter equation.
These molecular states appear as poles of the scattering amplitudes, and
several of them can be identified with the experimentally observed
states, including the , , ,
and . Also, for the recently reported
state, we find two poles with masses and widths remarkably close to the
experimental data, for both the and sectors.Comment: 27 pages, 24 tables, 2 figure
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