Related papers: The $Z_{cs}(3985)$ as a threshold effect from the …
We have studied the $J/\psi \phi$ mass distribution of the $B^+\to J/\psi\phi K^+$ reaction from threshold to about 4250 MeV, and find that one needs the contribution of the $X(4140)$ with a narrow width, together with the $X(4160)$ which…
In this talk we address two topics: The first one is an empirical explanation in terms of a new state $h_1$ of the peak in the $K^{*0}\bar{K}^{*0}$ invariant mass distribution close to threshold of this channel in the $J/\psi \to \eta…
We propose an explanation of the new resonances observed in $D_s^{(*)+} \pi^0$ decays. We suggest that the data can be explained by the mixing of conventional p-wave excited $D_s^+$ mesons with 4-quark states. The narrow states observed in…
The BESIII collaboration recently observed a charged hidden-charm structure with strangeness in the recoil mass spectrum of $K^+$ in the processes $e^+e^- \to D^-_s D^{*0} K^+$ or $D^{*-}_s D^0 K^+$, named as $Z_{cs}(3985)^-$. Within the…
I comment on a paper by Christoph Hanhart and Alexey Nefediev, published in Phys. Rev. D 106, 114003 (2022). The authors discuss the interpretation of mesons close to their lowest decay threshold and present a mechanism for the formation of…
We investigate near-threshold $J/\psi$ photoproduction off the nucleon, focusing on hadronic rescattering effects induced by open-charm meson-baryon intermediate states. Beyond the conventional Pomeron-exchange mechanism, the $\bar…
We study the charmed meson pair (${\bar D}^0 D^0$ and $D^- D^+$) production in ${\bar p}p$ annihilation within an effective Lagrangian model that has only the baryon-meson degrees of freedom and involves the physical hadron masses. The…
We analyze the decay modes $B^0 \to D^{*-} D^0 K^+$ and $B^0 \to D^{*-} D^{*0} K^+$ and, using the available experimental data, we find bounds for the constants g and h describing the strong coupling of heavy mesons to light pseudoscalar…
We discuss the production of $D \bar{D}$ pairs in $e^+ e^-$ collisions, where $D$ refers to either $D^0$ or $D^+$. The continuum mechanism with the $t/u$-channel vector-meson $D^*$ exchanges are considered. The results of the calculation…
The reaction $K^-p\rightarrow\Lambda\eta$ at low energies is studied with a chiral quark model approach. Good descriptions of the existing experimental data are obtained. It is found that $\Lambda(1670)$ dominates the reaction around…
Two coupled channel effects connected with kaon pair production in proton-proton collisions are discussed. (1) Although there is ample evidence that the antikaon is strongly attracted to the recoil protons in pp -> K+pK-p, residual effects…
Starting from the molecular picture for the $D_{s1}(2460)$ and $D_{s1}(2536)$ resonances, which are dynamically generated by the interaction of coupled channels, the most important of which are the $D^*K$ for the $D_{s1}(2460)$ and $DK^*$…
A model for the p d --> p d eta reaction published earlier, including the final state interaction (FSI) of all particles, is revisited to investigate the low energy data on this reaction. The three body problem of p-d-eta scattering in the…
A neutral structure in the $D\bar{D}^{*}$ system around the $D\bar{D}^{*}$ mass threshold is observed with a statistical significance greater than 10$\sigma$ in the processes $e^{+}e^{-}\rightarrow D^{+}D^{*-}\pi^{0}+c.c.$ and…
We perform a theoretical analysis of the $\Lambda_b \to J/\psi K^- p$ reaction from where a recent LHCb experiment extracts a $\Lambda(1405)$ contribution in the $K^- p$ spectrum close to threshold and two baryon states of hidden charm in…
We present a study of the $D^+\pi^-$, $D^0\pi^+$, and $D^{*+}\pi^-$ systems in inclusive $e^+e^- \rightarrow c\bar{c}$ interactions in a search for new excited $D$ meson states. We use a dataset, consisting of $\sim$454 fb$^{-1}$, collected…
We investigate $S$-wave coupled-channel effects in $e^+e^-$ annihilation in the energy region $\sqrt{s}\in[4.0,5.5]\,\mathrm{GeV}$, including the open-charm final states $\Lambda_c^+\bar{\Lambda}_c^-$, $\Xi_c^+\bar{\Xi}_c^-$,…
We report the observation of a new $D_{sJ}$ meson produced in $B^{+} \to \bar{D}^{0} D_{sJ} \to \bar{D}^{0} D^{0} K^{+}$. This state has a mass of $M=2708 \pm 9 ^{+11}_{-10} \rm{MeV}/{\it c}^{2}$, a width $\Gamma = 108 \pm 23 ^{+36}_{-31}…
To decode the near-threshold dynamics of the $X_{0,\,1}(4140)$ and $X_{1}(4685)$ states, we investigate the OZI-suppressed $\{D_{s}\bar{D}_{s},\, J/\psi \phi,\, D_{s}^{\ast}\bar{D}_{s}^{\ast}\}$ coupled-channel scattering in $B\to…
The spectral density of the $D$-meson in the nuclear environment is studied within a self-consistent coupled-channel approach assuming a separable potential for the bare meson-baryon interaction. The $DN$ interaction, described through a…