Related papers: Can low-lying Roper states be explained as antidec…
Motivated by recent experimental evidence for apparent $cc\bar c \bar c$ states at LHCb, CMS and ATLAS, we consider how the mass spectrum and decays of such states can be used to discriminate among their possible theoretical…
Within the collective quantization scheme for chiral solitons we discuss states in higher dimensional representations of flavor SU(3) and their relation to radially excited states in the octet. We also consider states which do not have…
I study the charmed $uudd\bar c$ resonance D*p (3100) very recently discovered by the H1 collaboration at Hera. An anticharmed resonance was already predicted, in a recent publication mostly dedicated to the S=1 resonance Theta+(1540). To…
Assuming that the recently observed hidden-charm pentaquark state, $P_c(4450)$, is of molecular nature as predicted in the unitary approach, we propose to study the decay of $\Xi^-_b\rightarrow J/\psi K^- \Lambda$ to search for the…
We study the large $N_c$ behavior of couplings among light meson states with different compositions in terms of quarks and gluons. We shortly review the most common compositions of mesons, which are of interest for the understanding of…
In present work, we investigate the spectrum of several low-lying $sscq\bar{q}$ pentaquark configurations employing the constituent quark model, within which the hyperfine interaction between quarks is taken to be mediated by Goldstone…
Some features and predictions of a recently proposed model based on diquark-antidiquark bound states are illustrated. Its ability in accomodating newly discovered charmed resonances around 4 GeV is discussed.
The hypothesis that there exists a nonet of scalars mainly composed of a valence quark-antiquark pair and mixed according to near singlet-octet separation : f_0 (980) singlet, a_0^{+,0,-} (980), K^{* +,0}_0 (1430), \bar K^{* -,0}_0 (1430),…
We construct the complete set of positive parity pentaquarks, which correspond in the quark model to {\bar s} q^{Nc+1} states with one unit of orbital angular momentum L=1. In the large Nc limit they fall into the K=1/2 and K=3/2 irreps…
We study the masses of open charm and bottom tetraquark states within the diquark-antidiquark scenario in the relativized quark model proposed by Godfrey and Isgur. The diquark and antidiquark masses are firstly solved by relativized quark…
Interpreting the recently discovered narrow exotic baryons as pentaquark states, we discuss, along an old argument of ours, the isospin mixing occurring within the two doublets of $Q = -1$ and Q=0 states lying inside the $S=-2$…
The spectra of pentaquarks, some of them being observed recently, are discussed within topological soliton model and compared with simplified quark picture. Results obtained within chiral soliton model depend to some extent on the…
We have done the exploratory study of bottom tetraquarks ($[bq\bar b \bar q];{q\in u,d}$) in the diquark-antidiquark framework with the inclusion of spin hyperfine, spin-orbit and tensor components of the one gluon exchange interaction. Our…
The group classification of exotic pentaquarks involving four standard quarks and a single antiquark to produce pentaquarks of strangeness +1 is outlined.
We discuss the possibility that the two nearby resonances observed by BESIII partially below the \,$p\bar p$\, threshold might be due to mixing between two metastable states with the same $J^{PC}=0^{-+}$ quantum numbers, but rather…
Experimentally several charged axial-vector hidden-charm states were reported. Within the framework of the color-magnetic interaction, we have systematically considered the mass spectrum of the hidden-charm and hidden-bottom tetraquark…
We consider the production and decay of multiquark systems in the framework of string models where the hadron structure is determined by valence quarks together with string junctions. We show that the low mass multiquark resonances can be…
It is explained why the interpretation of the resonances $f_{2}(1270),$ $a_{1}(1260)$ and $f_{0}(1370)$ as quark-antiquark states is legitimate. The result of the quark model and of recently performed Bethe-Salpeter studies are not…
Heavy quark symmetries are useful for predicting the existence of heavy states, their masses, and spin states. Despite numerous studies on the $P_{c\bar{c}}(4440)$ and $P_{c\bar{c}}(4457)$ heavy states, their spin states have not been…
Recently, the LHCb Collaboration have updated their analysis of the resonant $J/\psi p$ mass spectrum in the decay $\Lambda_b^0 \to J/\psi p K^-$. In the combined Run~1 and Run~2 LHCb data, three peaks are observed, with the former…