scholarly journals Symmetries, Partners and Thresholds: The Case of the Xb

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1600
Author(s):  
Pablo G. Ortega ◽  
David R. Entem ◽  
Francisco Fernández
Keyword(s):  
Spin Symmetry ◽  
Heavy Meson ◽  
Flavor Symmetry ◽  
Heavy Flavor ◽  
Coupled Channels ◽  
Quark Spin ◽  
Meson Spectroscopy ◽  
New States ◽  
Heavy Quark Spin Symmetry ◽  
Quark Models

The discovery of the X(3872) meant the revival of the heavy meson spectroscopy beyond naive qq¯ structures. Since the SU(3) scheme, which was very useful in the dawn of the quark models, does not work for these states, one has to use new symmetries, like Heavy Quark Spin Symmetry (HQSS) and Heavy Flavor Symmetry (HFS), to look for new states. However, at the energy regions where these new states appear, new factors are involved and it is not straightforward to relate the predictions of the symmetries with the data. In this work, we present a critical analysis of this problem and show, in a coupled-channels model, how the relative position of the bare QQ¯ states with respect to meson-meson thresholds and the coupling with other channels modulate the strength of the interaction and, hence, modify the structure of the predicted states. We found a possible candidate to the X(3872) partner at 10,599 MeV/c2.

scholarly journals CHARMING BARYONS

2014 ◽  
Vol 26 ◽  
pp. 1460124
Author(s):  
C. GARCIA-RECIO ◽  
L. L. SALCEDO ◽  
D. GAMERMANN ◽  
J. NIEVES ◽  
O. ROMANETS ◽  
...  
Keyword(s):  
Heavy Quark ◽  
Spin Symmetry ◽  
Flavor Symmetry ◽  
Minimal Extension ◽  
Heavy Flavor ◽  
Vector Mesons ◽  
Quark Spin ◽  
Heavy Quark Spin Symmetry ◽  
Experimental Values

We study odd-parity baryonic resonances with one heavy and three light flavors, dynamically generated by meson-baryon interactions. Special attention is paid to Heavy Quark Spin Symmetry (HQSS), hence pseudoscalar and vector mesons and baryons with Jπ = 1/2+ and 3/2+ are considered as constituent hadrons. For the hidden-charm sector ([Formula: see text]), the meson-baryon Lagrangian with Heavy Flavor Symmetry is constructed by a minimal extension of the SU(3) Weinberg-Tomozawa (WT) Lagrangian to fulfill HQSS, such that not new parameters are needed. This interaction can be presented in different formal ways: as a Field Lagrangian, as Hadron creation-annihilation operators, as SU(6)×HQSS group projectors and as multichannel matrices. The multichannel Bethe-Salpeter equation is solved for odd-parity light baryons, hidden-charm N and Δ and Beauty Baryons (Λb). Results of calculations with this model are shown in comparison with other models and experimental values for baryonic resonances.

scholarly journals N AND Δ HIDDEN-CHARM RESONANCES WITH HEAVY-QUARK SPIN SYMMETRY

2014 ◽  
Vol 26 ◽  
pp. 1460108
Author(s):  
OLENA ROMANETS ◽  
CARMEN GARCÍA-RECIO ◽  
LORENZO LUIS SALCEDO ◽  
JUAN NIEVES ◽  
LAURA TOLÓS
Keyword(s):  
Heavy Quark ◽  
Bound States ◽  
Wave Interaction ◽  
Spin Symmetry ◽  
S Wave ◽  
Coupled Channels ◽  
Quark Spin ◽  
Charm Baryon ◽  
Heavy Quark Spin Symmetry ◽  
Baryon Resonances

We study N and Δ hidden-charm baryon resonances that are generated dynamically from the s-wave interaction of pseudoscalar and vector mesons with 1/2+ and 3/2+ baryons. We use a unitary coupled-channels model that fulfills heavy-quark spin symmetry and respects spin-flavor symmetry in the light sector. We predict seven N-like and five Δ-like states with masses around 4 GeV, most of them as bound states. Some of these states form heavy-quark spin multiplets, which are almost degenerate in mass.

scholarly journals Light flavor and heavy quark spin symmetry in heavy meson molecules

2013 ◽  
Vol 87 (7) ◽  
Author(s):  
C. Hidalgo-Duque ◽  
J. Nieves ◽  
M. Pavón Valderrama
Keyword(s):  
Heavy Quark ◽  
Spin Symmetry ◽  
Heavy Meson ◽  
Quark Spin ◽  
Heavy Quark Spin Symmetry

scholarly journals STATUS OF CHIRAL DOUBLERS OF HEAVY-LIGHT HADRONS IN LIGHT OF RECENT BABAR, CLEO, BELLE AND SELEX Ds STATES

2005 ◽  
Vol 20 (02n03) ◽  
pp. 229-239 ◽  
Author(s):  
MACIEJ A. NOWAK
Keyword(s):  
Heavy Quark ◽  
Chiral Symmetry ◽  
Main Idea ◽  
Spin Symmetry ◽  
Spin Parity ◽  
Quark Spin ◽  
New States ◽  
Heavy Quark Spin Symmetry ◽  
Effective Theories ◽  
Chiral Partner

We explain the main idea of the chiral doublers scenario, originating from simultaneous constraints of chiral symmetry and of heavy quark spin symmetry on effective theories of heavy-light hadrons. In particular we discuss chiral doublers for mesons, chiral doublers for excited mesons, chiral doublers for baryons and chiral doublers for excited baryons. We point out the arguments why new states Ds(2317) and Ds(2457) might be viewed as chiral doublers of Ds and [Formula: see text]. Then we comment on non-strange mesons D0(2308) and D′1(2427) observed by Belle and Focus, and on Θc(3099) signal observed by H1. Finally, we point out that very recent discovery by SELEX of Ds(2632), if confirmed by other experiments and if spin-parity of this state is 1-, may be interpreted as a signal for chiral doubler of Ds1(2536). Such an identification implies another narrow, spin-parity 2-Ds state ca 37 MeV above the new 1-, corresponding to chiral partner of Ds2.

Sign in / Sign up

Export Citation Format

Share Document