Related papers: A multiquark description of the $D_{sJ}(2860)$ and…
I briefly introduce the status of charm physics and I discuss the case of the meson with open charm $D_{sJ}(2700)$.
Possible $2S$ and $1D$ excited $D$ and $D_s$ states are studied, the charmed states $D(2550)^0$, $D^\ast(2600)$, $D(2750)^0$ and $D^\ast(2760)$ newly observed by the BaBar Collaboration are analyzed. The masses of these states are explored…
We analyze various possible interpretations of the narrow state $D_{sJ}(2632)$ which lies 100 MeV above threshold. This interesting state decays mainly into $D_s \eta$ instead of $D^0 K^+$. If this relative branching ratio is further…
Motivated by recent experimental evidence for apparent $cc\bar c \bar c$ states at LHCb, CMS and ATLAS, we consider how the mass spectrum and decays of such states can be used to discriminate among their possible theoretical…
We use the QCD sum rules to analize the hadronic decay $D_{sJ}^{+}(2317)\to D_s^+\pi^0$, in the hypotesis that the $D_{sJ}^{+}(2317)$ can be identified as a four-quark state. We use a diquak-antidiquark current and work to the order of…
The spectrum of the $c qq$ baryons contains a few states whose nature is not clearly a three-quark composite and which might have a sizable baryon-meson component. Examples include the $\Sigma_c(2800)$ or the $\Lambda_c(2940)$. Here we…
The \Lambda_c(2940)^+ baryon is studied in a constituent quark model as a molecular state composed by nucleons and D^* mesons. A bound state with the right binding energy is found for the J^\pi=3/2^- channel. The partial widths…
We study radiative decays of $D^*_{sJ}(2317)$ and $D_{sJ}(2460)$ using light-cone QCD sum rules. In particular, we consider the decay modes $D^*_{sJ}(2317)\to D_s^* \gamma $ and $D_{sJ}(2460)\to D_s^{(*)} \gamma, D^*_{sJ}(2317) \gamma$ and…
In the framework of the improved chromomagnetic interaction model, we complete a systematic study of the $S$-wave tetraquark states $Qq\bar{Q}\bar{q}$ ($Q=c,b$, and $q=u,d,s$) with different quantum numbers, $J^{PC}=0^{+(+)}$, $1^{+(\pm)}$,…
In order to classify the charmed-strange mesons, including puzzling D_{s0}^{*}(2317) and D_{s1}(2460), and recently observed D_{s1}^{*}(2710) and D_{sJ}^{*}(2860), we employ the U~(12)*O(3,1) level-classification scheme of hadrons proposed…
We study heavy-light meson resonances with quantum numbers J^P=0^+ and J^P=1^+ in terms of the non-linear chiral SU(3) Lagrangian. Adjusting the free parameters that arise at subleading order to reproduce the mass of the D(2420) resonance…
The properties of the $\DsTT$ and $\DsFE$ mesons are studied using 125 ${\rm fb}^{-1}$ of $e^+e^- \to c \bar{c}$ data collected by the BaBar experiment. Preliminary mass estimates of $[2318.9\pm 0.3 ({\rm stat.}) \pm 0.9 ({\rm syst.})]$…
In a recent paper by N. Santowsky et al. [Phys. Rev. D 102, 056014 (2020)], covariant coupled equations were derived to describe a tetraquark in terms of a mix of four-quark states $2q 2\bar{q}$ and two-quark states $q\bar{q}$. These…
We discuss a possible interpretation of the open charm mesons $D_{s0}^*(2317)$, $D_{s1}(2460)$ and the hidden charm mesons X(3872), Y(3940) and Y(4140) as hadron molecules. Using a phenomenological Lagrangian approach we review the strong…
The ${q}\bar{q}$ spectrum is studied within a chiral constituent quark model. It provides with a good fit of the available experimental data from light (vector and pseudoscalar) to heavy mesons. The new $D$ states measured at different…
In this article, we study the strong decays of the newly observed charmed mesons $D(2550)$, $D(2600)$, $D(2750)$ and $D(2760)$ with the heavy quark effective theory in the leading order approximation, and tentatively identify the…
We study the decay properties of a $D(2900)$ state, with spin-parity $0^-$, whose existence was proposed in an earlier study of the $D K\bar K$ and coupled channel system. It was found in the former work that a $D$-meson appears with a mass…
In this work, a study of the $D_s\bar{D}_s$ interaction and its couplings to the channels $D\bar{D}$ and $J/\psi \phi$ is performed in a quasipotential Bethe-Salpeter equation approach. The $D_s^+{D}_s^-$ and $D^+{D}^-$ invariant mass…
The newly observed $X, Y, Z$ exotic states are definitely not in the standard $Q\bar Q'$ structures, thus their existence composes a challenge to our understanding on the fundamental principles of hadron physics. Therefore the studies on…
We study the decay widths of the narrow resonances $D_{sj}^*(2317)$ and $D_{sj}(2460)$ in the chiral quark model, together with the well-known $D^\ast$ and $D_s^*$ mesons. All the parameters in our calculation are taken from Godfrey and…