Related papers: Puzzles in charmonium decays
In this presentation, we discuss the recent hadronic decays of charmed mesons observed in the BESIII experiment, specifically focusing on the decay processes $D^+ \to K_S^0 \pi^+ \eta$, $D^0 \to \pi^+ \pi^- \eta$, $D^+ \to \pi^+ \pi^0…
In previous publications we have analyzed the strong and electromagnetic decays of heavy mesons and heavy baryons in a formalism which incorporates heavy-quark and chiral symmetries. There are two possible symmetry-breaking effects on the…
We identify open charm effects in a direct production process $e^+e^-\to J/\psi \pi^0$. A unique feature of this process is that the $D\bar{D}^*+c.c.$ threshold is located at a relatively isolated energy region, i.e. $\sim 3.876 \…
The discovery of numerous new charmonium-like structures since 2003 have revitalized interest in exotic meson spectroscopy. These structures do not fit easily into the conventional charmonium model, and proposals like four-quark states,…
We present recent LHCb results and future prospects for CP violation and mixing measurements in multi-body charm decays. The complex amplitude structure of multi-body decays provides unique sensitivity to CP violation localised in certain…
Here we discuss three separate topics in charmonium physics. (1) The Omicron \OMC as $1^{--}$ trigluonia, and the charmonium puzzle; the $\eta_c' (3600)$ search. (2) The decay $\psi(^1P_1) \to \pi^o + J/\psi$ and isospin violating…
Recent results from BES and CLEOc experiments on hadron spectroscopy and charmonium decays using J/psi, psi' and psi'' data samples collected in e+e- annihilation are reviewed, including the observation of X(1835) in J/psi --> gamma pi+ pi-…
We survey some prospects of identifying further in-medium modifications of hadrons in a strongly interacting medium with respect to ongoing experiment series of the HADES Collaboration and planned experiments of the CBM Collaboration at…
Hadron resonances affect nonexotic $D^o$ decays but not $B$ decays which are far from the resonance region. We obtain new information from {\bf exclusive} decays and show that interference between colour favoured and colour suppressed…
The hadronic decays of $\chi_{c1}\to VV$ and $\chi_{c2}\to VP$ are supposed to be suppressed by the helicity selection rule in the pQCD framework. With an effective Lagrangian method, we show that the intermediate charmed meson loops can…
The LHCb experiment has collected the world's largest sample of charmed hadrons. This sample is used to measure observables related to $D^0 -\overline{D}^0$ mixing, direct $C\!P$ violation and $C\!P$ violation in mixing and interference in…
I introduce an entirely new dynamical description for exotic charmoniumlike hadrons, based upon the competing effects of the strong attraction between quarks in a diquark, and the inability of the diquark to hadronize on its own due to…
We propose to study the open charm effects in $e^+ e^-\to J/\psi\eta$, $J/\psi\pi^0$ and $\phi\eta_c$. We show that the exclusive cross section lineshapes of these processes would be strongly affected by the open charm effects. Since the…
We present recent results in semileptonic and non-leptonic exclusive $B_c$ decays to charmonium states both in $S$-wave, $J/\psi$ and $\eta_c$, and in $P$-wave, $\chi_{cJ}$ and $h_c$. The analysis, based on the heavy quark spin symmetry…
The experimental observation indicates that the branching ratio of $\psi'\to \rho\pi$ is very small while the $\rho-\pi$ channel is a main one in $J/\psi$ decays. To understand the puzzle, various interpretations have been proposed.…
The E1 transitions of $\psi(3686)$ and $\psi(3770)\to \gamma\chi_{cJ}$ are investigated in a non-relativistic effective field theory (NREFT) where the open charm effects are included systematically as the leading corrections. It also allows…
After sketching heavy quark expansions as applied to heavy flavour decays I emphasize the relevance of nonperturbative dynamics at the charm scale for exclusive $b\to c$ modes. I address the issue of quark-hadron duality for charm and…
The masses and decay widths of charmonium states are studied in the presence of strong magnetic fields. The mixing between the pseudoscalar and vector charmonium states at rest is observed to lead to appreciable negative (positive) shifts…
In this work, we predict two charged charmonium-like structures close to the $D^\ast\bar{D}$ and $D^\ast\bar{D}^\ast$ thresholds, where the Initial Single Pion Emission mechanism is introduced in the hidden-charm dipion decays of higher…
It is demonstrated that charm is systematically undercounted in various experiments. Via a process of elimination, $B(D^0 \rightarrow K^- \pi^+ )$ is identified as the culprit. It calibrates essentially all charmed meson production and…