Related papers: On the possibility to observe higher $n^3D_1$ bott…
A search is presented for new high-mass resonances decaying into electron or muon pairs. The search uses proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the CMS experiment at the LHC in 2016, corresponding to…
Using 4.7 fb^-1 of data taken at CESR at energies at and near the Upsilon(4S) we have studied the decay B- -> D{*+}pi-pi- (and its conjugate). We observe a new, broad charmed meson state, which we interpret as D_J(j=1/2), in its decay to…
The analysis of the nine 1-fold differential cross sections for the $\gamma_{r,v} p \to \pi^+\pi^-p$ photo- and electroproduction reactions obtained with the CLAS detector at Jefferson Laboratory was carried out with the goal to establish…
We investigate spectral features of bottomonium at high temperature, in particular the thermal mass shift and width of ground state S-wave and P-wave state. We employ and compare a range of methods for determining these features from…
The masses of $1^{--}$ P-wave charmonium-like and bottomonium-like tetraquark states are calculated in a constituent quark model (CQM) where the Cornell-like potential and Breit-Fermi interaction are employed. All model parameters were…
The possible hadronic molecules in $D_s^{(*)+}\Xi_c^{(',*)}$ systems with $J^P=1/2^-,3/2^-$ and $5/2^-$ are investigated with interactions described by light meson exchanges. By varying the cutoff in a phenomenologically reasonable range of…
Based on the non-relativistic QCD factorization scheme, we study the hadroproduction of the bottomonium states $\Upsilon(5S)$ and $\Upsilon(6S)$. We argue to search for them in the final states $\Upsilon(1S,2S,3S)\pi^+\pi^-$, which are…
We study the changes in the partial decay widths of excited charmonium states into $D \bar{D}$, when the D meson mass decreases in nuclear matter, taking the internal structure of the hadrons into account. Calculations within the 3P0 model…
Cross sections, beam asymmetries, and recoil polarisations for the reactions gamma p to K^+ Lambda ; gamma to K^+ Sigma^0, and gamma p to K^0 Sigma^+ have been measured by the SAPHIR, CLAS, and LEPS collaborations with high statistics and…
We report a measurement of the exclusive e+e- -->Lambda_c+ Lambda_c- cross section as a function of center-of-mass energy near the Lambda_c+ Lambda_c- threshold. A clear peak with a significance of 8.2 sigma is observed in the Lambda_c+…
We review the studies of transitions and decays of bottomonium states from the e+ e- data recorded by the Belle detector at various Upsilon-resonances. We also report a recent study of the branching fractions of \chi_{bJ}(1P) to 41 hadronic…
Very recently, the {\it BABAR} Collaboration indicated that there exist an explicit enhancement structure near 2.2 GeV when focusing on the $e^+e^-\to\pi^+\pi^-$ process again, which inspires our interest in studying the production of…
In this work, we study higher bottomonia up to the $nL=8S$, $6P$, $5D$, $4F$, $3G$ multiplets using the modified Godfrey-Isgur (GI) model, which takes account of color screening effects. The calculated mass spectra of bottomonium states are…
Motivated by the updated analysis of the $G(3900)$ by the BESIII collaboration, we perform a global analysis of the cross sections of the $e^+e^-\to D\bar{D}$, $e^+e^-\to D\bar{D}^*+c.c.$, $e^+e^-\to D^*\bar{D}^*$ processes, especially…
We study some possible experimental consequences of new physics on the spectrum and decays of bottomonium states below $B\bar{B}$ threshold. In addition to lepton universality breaking in Upsilon decays, large widths of pseudoscalar…
Heavy quark spin symmetry is useful to make predictions on ratios of decay or production rates of systems involving heavy quarks. The breaking of spin symmetry is generally of the order of $O({\Lambda_{\rm QCD}/m_Q})$, with $\Lambda_{\rm…
New enhancements in the charmonium and bottomonium spectra observed since 2003 are very briefly reviewed. Special attention is paid to $\chi_{c1}(3872)$ (formerly $X(3872)$) owing to its remarkable proximity to the $\bar{D}^{\star0}\!D^0$…
We discuss a set of precision observables that can probe the existence of a light particle $X$ coupled to electrons in the mass range of 1-100 MeV. As a case study, we consider the recent excess of $e^+e^-$ final-state events at $\sqrt{s} =…
Observations of new charmonium(-like) and bottomonium(-like) states (sometimes refered to as "XYZ" states) at e+e- colliders have changed our picture of quarkonia systems as QCD bound states. Potential models with a linear confinement…
Recent progress on the bottomonium states is reported. This talk briefly reviews the observation of $h_b(1P), h_b(2P), Z_{b1}^+, Z_{b2}^+$ states, transition of $h_b(nP)\to \eta_b(mS)\gamma$ and new studies on the $\eta_b(2S)$ state. Other…