Description
Discussion leader: Pietro Faccioli
The two heavy quark combinations cc, bb and bc unifies with s quark in case of three doubly heavy $\Omega$ baryons, while for six doubly heavy Ξ baryons light quarks u or d are combined. The ground, radial, and orbital states are calculated in the framework of the hypercentral constituent quark model with Coulomb plus linear potential. The different approaches and their predicted masses of...
In this talk, I will review some new theoretical and experimental developments on doubly heavy baryons as well as tetraquarks and pentaquarks made of double heavy quarks, by insisting on our recent studies. I will compare the predictions of the phenomenological models with the experimental data on some parameters of the hadronic states under discussion. I will also discuss different...
Hadron formation is one of the most interesting open problems within the context of QCD. Understanding how the quarks bind with each other implies combining complex analytical perturbative calculations with not-yet-understood non-perturbative aspects. Quarkonia are the simplest quark-antiquark bound states and provide an ideal window to probe hadron formation. The high quality quarkonium...
Measurements made at the LHC have shown that the production of the J/psi, psi(2S), Upsilon(1S) and Upsilon(2S) quarkonia is suppressed in Pb–Pb collisions, with respect to the extrapolation of the pp production yields. The psi(2S) and Upsilon(2S) states are more strongly suppressed than the ground states and the level of the suppression changes with the centrality of the collision.
We show...
We compute the color singlet and color octet NRQCD long-distance matrix elements for inclusive production of P-wave quarkonia in the framework of potential nonrelativistic QCD. In this way, the color octet NRQCD long-distance matrix element can be determined without relying on measured cross section data, which has not been possible so far. We obtain inclusive cross sections of χcJ and χbJ at...
In this talk, I will introduce our investigations on the fully-heavy tetraquark states, including the calculations of their mass spectra and their strong decays into di-charmonia. Our calculations of the masses for the fully-heavy tetra quarks have been done several years before the recent LHCb's observation in the di-$J/\psi$ structure. However, our results suggest that the broad structure...
In this talk I will review our recent lattice results on the charmonia & bottomonia spectral functions and heavy-quark transport properties in hot medium. The spectral analyses are performed on the quarkonium correlators measured on the lattice extrapolated to the continuum limit and interpolated to physical $J/\psi$ and $\Upsilon$ masses. Good agreement is observed between our lattice data...
We give a review of the calculations of the masses of tetraquarks with two and four heavy quarks in the framework of the relativistic diquark-antidiquark model based on the quasipotential approach. Quasipotentials of quark-quark and diquark-antidiquark interactions are constructed similarly to previous studies of mesons and baryons. All parameters of the model were fixed by meson and baryon...
The $\Upsilon(nS)$ production and polarization at high energies is studied in the framework of $k_T$-factorization approach. Our consideration is based on the non-relativistic QCD formalism for bound states formation and off-shell production amplitudes for hard partonic subprocesses. The direct production mechanism and feed-down contributions from radiative $\chi_b(mP)$ decays are taken into...
The LHCb collaboration has observed a decrease with multiplicity of the ratio of the prompt production rates of $X(3872)$ and $\psi(2S)$ in pp collisions. We show that this observation can be explained by the scattering of comoving pions from $X(3872)$ if it is a weakly bound charm-meson molecule.
We compute the suppression and elliptic flow of bottomonium using real-time solutions to the Schroedinger equation with a realistic in-medium complex-valued potential. To model the initial production, we assume that, in the limit of heavy quark masses, the wave-function can be described by a lattice-smeared (Gaussian) Dirac delta wave-function. The resulting final-state quantum-mechanical...
I will discuss the properties of $\Upsilon(nS)$ bottomonium states as well as the properties of $\chi_b(nS)$ bottomonium states at non-zero temperature using lattice NRQCD. In this study $48^3 \times 12$ lattices are used with highly improved staggered quark (HISQ) action with physical strange quark and light quark masses corresponding to the pion mass of 160 MeV in the continuum limit....
