Related papers: Understanding the Charged Meson Z(4430)
We look for the existence of stable (by strong interactions) tetraquarks, mesons containing two heavy antiquarks and two light quarks, specifically a $|{\bar b}{\bar b}qq\rangle$ state. This state is viewed as two $|{\bar b}q\rangle $…
In the framework of the quark delocalization color screening model, we investigate tetraquarks composed of $us\bar{d}\bar{b}$ and $ud\bar{s}\bar{b}$ in two structures: meson-meson structure and diquark-antidiquark structure. Neither bound…
After Y(4630) is discovered, theorists have given various explanations. We find that if Y(4630) is interpreted as the D-wave resonant state of $\Lambda_c \bar {\Lambda}_c$ system, the particle mass, decay width and all quantum numbers are…
Motivated by the recent observations of exotic open-charm tetraquark candidates \(T^a_{c\bar{s}0}(2900)^{++}\) and \(T^a_{c\bar{s}0}(2900)^{0}\), we systematically calculate the mass spectra of \([cq][\bar{s}\bar{q}]\) tetraquarks within a…
We calculate the masses of the $QQ\bar{q}\bar{q}$ ($Q=c,b$; $q=u,d,s$) tetraquark states with the aid of heavy diquark-antiquark symmetry (HDAS) and the chromomagnetic interaction (CMI) model. The masses of the highest-spin ($J=2$)…
We consider the implications from the possibility that the recently observed state X(3872) is a meson-antimeson molecule. We write an effective Lagrangian consistent with the heavy-quark and chiral symmetries needed to describe X(3872). We…
Motivated by the recently observation of the tetraquark $T_{cc}^+ $ state, in this work I revisit the Heavy-Meson Effective Theory to perform a simplified field-theoretical study of possible deuteron-like $D^{(\ast)} D ^{(\ast)},…
We calculate the scattering amplitudes of Goldstone bosons off the pseudoscalar D-mesons in unitarized heavy meson chiral approach. The low energy constants appearing in $\mathcal{O}(p^2)$ chiral Lagrangian are determined by fitting lattice…
Exploration of the resonances $Z_c(3900)$ and $Z(4430)$ are performed by assuming that they are ground-state and first radial excitation of the same tetraquark with $J^{P}=1^{+}$. The mass and current coupling of the $ Z_c(3900)$ and…
In the framework of the quark delocalization color screening model (QDCSM), we systematically investigate the double-charm and double-strange tetraquark systems $cc\bar{s}\bar{s}$ with two structures: meson-meson and diquark-antidiquark.…
We discuss a possible interpretation of the Ds1(2460) meson as a hadronic molecule - a bound state of D* and K mesons. Using a phenomenological Lagrangian approach we determine the strong Ds1 to Ds* pi0 and radiative Ds1 to Ds gamma decays.…
A survey of the experimental, phenomenological, and theoretical status of the new heavy mesons is presented. States discussed are the $B_c$, $h_c$, $\eta_c'$, $D_s(2317)$, $D_s(2460)$, X(3872), X(3940), Y(3940), Z(3930), and Y(4260). Quark…
We investigate whether the newly observed narrow resonance $Z_{c}(4025)$ can be described as a $D^{*}\bar{D^{*}}$ molecular state with quantum numbers $J^{P}=1^{+}$. Using QCD sum rules, we consider contributions up to dimension six in the…
Whether molecular states indeed exist in nature has been disputed for a long time. Several new resonances have been observed in the recent experiments and they seem to be of exotic structures and some of them have been proposed to be…
In this work, we perform a systematic investigation of the hidden-charm tetraquark states with $I^G(J^{PC})=1^+(1^{+-})$ within the hadronic molecular picture, placing particular emphasis on systems composed of an $S$-wave $(D, D^*)$ meson…
In this article, we assume that there exists a scalar hidden charm tetraquark state in the $\pi^+ \chi_{c1}$ invariant mass distribution, and study its mass using the QCD sum rules. The numerical result $M_{Z}=(4.36\pm0.18) \rm{GeV}$ is…
Inspired by the observation of the $P_{cs} (4459)$ state by LHCb recently, we reexamine the results of the interaction of the $J/\psi \Lambda$ channel with its coupled channels, exploiting the coupled channel unitary approach combined with…
The observation of the two states $P_c(4380)$ and $P_c(4445)$ [Phys.Rev.Lett. 115 (2015) 072001] solids the existence of the pentaquark state in Nature. In this work, we study the spectrum of the pentaquark states including one or two heavy…
The heavy hadron spectrum is constrained by symmetries, of which two of the most important ones are heavy-quark spin and SU(3)-flavor symmetries. Here we argue that in the molecular picture the $Y(4230)$ (or $Y(4260)$), the $Y(4360)$ and…
Following the recent confirmation of the Z+(4430) resonance with J^{PG}=1^{++}, we have re-examined the model of S- and P-wave tetraquarks. We propose a `type-II' diquark-antidiquark model which shows to be very effective at producing a…