Related papers: Inter quark mass split and a proposed possible 5 q…
Recently LHCb reported the discovery of five extremely narrow excited $\Omega_c$ baryons decaying into $\Xi_c^+ K^-$. We interpret these baryons as bound states of a $c$-quark and a $P$-wave $ss$-diquark. For such a system there are exactly…
Using a quite accurate flavour-independence of $nS$-level mass differences in heavy quarkonia and a corresponding quasiclassical expression for the heavy quark binding energy, one shows that experimental data on masses of mesons with heavy…
We present a lattice QCD calculation of the ground-state energy shifts of various baryons in a medium of pions or kaons at a single value of the quark mass corresponding to a pion mass of m_\pi~390 MeV and a kaon mass of m_K~540 MeV, and in…
The recent reported charmed-strange resonance at 2.32 GeV/c suggests a possible multiquark state. Three types of multiquark bound states are reviewed. A previous model-independent variational approach considers a tetraquark with two heavy…
The recent observation by CDF of Sigma_b^{+-} (uub and ddb) baryons within 2 MeV of the predicted Sigma_b - Lambda_b splitting has provided strong confirmation for the theoretical approach based on modeling the color hyperfine interaction.…
We perform a constituent quark model analysis for the masses of the doubly heavy tetraquark states $T_{QQ}$ after we fix the parameters to fit the masses of the newly observed $\Xi_{cc}^{++}$ and hadrons involving heavy quarks relevant to…
Recent lattice QCD calculations from the HAL and NPLQCD Collaborations have reported evidence for the existence of a bound state with strangeness -2 and baryon number 2 at quark masses somewhat higher than the physical values. A controlled…
A dynamical calculation of pentaquark systems with quark contents $uudd\bar{s}$ is performed in the framework of quark delocalization color screening model with the help of resonating group method. The effective potentials between baryon…
We investigate light meson bound state contributions to six quark Green's functions and establish that the latter has poles corresponding to baryon bound states. We estimate light baryon masses including the Roper resonance. Constituent…
In this presentation we discuss the generation of hadrons with an exotic quark content and hidden charm emerging from three-body interactions. To be more specific, we have studied the $KD\bar{D}^*/K\bar D D^*$ and $ND\bar{D}^*/N\bar{D}D^*$…
We present a model to compute baryon and meson transverse momentum distributions, and their ratios, in relativistic heavy-ion collisions. The model allows to compute the probability to form colorless bound states of either two or three…
The existence of a shallow or virtual tetraquark state, $cc\bar{u}\bar{d}$, is discussed. Using the putative masses for the doubly charmed baryons ($ccu/ccd$) from SELEX, the mass of the $cc\bar{u}\bar{d}$ state is estimated to be about…
Recently a novel hadronic state of mass 6.9 GeV, that decays mainly to a pair of charmonia, was observed in LHCb. The data also reveals a broader structure centered around 6490 MeV and suggests another unconfirmed resonance centered at…
A narrow resonance in D*- p and D*+ pbar invariant mass combinations is observed in inelastic electron-proton collisions at centre-of-mass energies of 300 GeV and 320 GeV at HERA. The resonance has a mass of 3099 \pm 3 (stat.) \pm 5 (syst.)…
Motivated by the recent surprising discovery of two new meson states with c s-bar quark content but unexpectedly low masses and narrow total decay widths, we work out, in a nonrelativistic potential-model approach developed already some two…
QCD-motivated models for hadrons predict an assortment of "exotic" hadrons that have structures that are more complex than the quark-antiquark mesons and three-quark baryons of the original quark-parton model. These include pentaquark…
The relativistic six-quark equations including the $u$, $d$ quarks and antiquarks are found. The nonstrange baryonia $B \bar B$ are constructed without the mixing of the quarks and antiquarks. The relativistic six-quark amplitudes of the…
Using phenomenological formulae, we can deduce the rest masses and intrinsic quantum numbers (I, S, C, B and Q) of quarks, baryons and mesons from only one unflavored elementary quark family. The deduced quantum numbers match experimental…
The masses of the yet undiscovered baryons containing single $c$ or $b$ quarks are estimated from the known masses using the following rules: equal distances in mass between the isomultiplets forming sextets, equal mass differences between…
The pentaquark state recently discovered has been discussed based on various quark model calculations. Odd parity for the state can not be ruled out theoretically because contributions related to non-trivial color structures have not been…