相关论文: QCD Inequalities and the $D_s(2320)$
The $X17$ particle, discovered by Krasznahorkay et al. at ATOMKI, was recently confirmed in the $\gamma \gamma$ invariant mass spectra by Abraamyan et al. at JINR. We notice with surprise and interest that the $X17$ seems to have a…
In this article, we assume that there exists a scalar $D_s^\ast {\bar D}_s^\ast$ molecular state in the $J/\psi \phi$ invariant mass distribution, and study its mass using the QCD sum rules. The predictions depend heavily on the two…
We generalise the framework of Dyson-Schwinger and Bethe-Salpeter equations for four-quark states to accommodate the case of unequal quark masses. As a first application, we consider the quantum numbers $I(J^{PC})=0(1^{++})$ of the…
We suggest that the recently observed charmed scalar mesons $D_0^{0}(2308)$ (BELLE) and $D_0^{0,+}(2405)$ (FOCUS) are considered as different resonances. Using the QCD sum rule approach we investigate the possible four-quark structure of…
The recently discovered charmed-strangemeson Ds0*(2317) has been speculated to be a tetraquark mesonium. We study this suggestion with overlap fermions on 2+1 flavor domain wall fermion configurations. We use 4-quark interpolating…
In this article, we assume that there exist the pseudoscalar $D\bar{D}_{s0}^*(2317)$ and $D^*\bar{D}_{s1}^*(2460)$ molecular states $Z_{1,2}$ and construct the color singlet-singlet molecule-type interpolating currents to study their masses…
The experimental status of the recently observed resonances which could be interpreted as c$\bar q$ mesons with s$_l^P={1/2}^+$ is reviewed. In the framework of HQET and chiral perturbation theory, strong and radiative widths of these…
We consider the nonleptonic B decays $ B \to D^{(*)} D_s(2317)$ and $ B \to D^{(*)} D_s(2460)$, involving the newly discovered $D_s(2317)$ and the $D_s(2460)$ states. We find that experiments indicate disagreement with model calculations of…
The masses of the $D_{sj}^\ast$(2317)and $D_{sj}^\ast$(2463) were found in the MIT bag model in a reasonable agreement with the experimental values. The spectrum of ${0^\pm,1^\pm}$ for $D$ and $B$ mesons is presented. The equalities between…
We report the observation of a new DsJ meson produced in B+ -> D0-bar DsJ -> D0-bar D0 K+. This state has a mass of M = 2715 +-11(stat) +11-14(syst) MeV/c^2, a width Gamma = 115 +-20(stat) +36-32(syst) MeV/c^2 and a spin-parity 1-. The…
If one of the recently discovered charmed-strange mesons (D_sJ(2317)) is the 0+ state of cs-bar, the other (D_sJ(2460)) is most likely the 1+ state with j=1/2. They could be produced in e+e- annihilation by fragmentation from cc-bar jets or…
We conduct systematic calculations of the S-wave fully strange systems with ``normal" $\left(J^{P C}=0^{++}, 1^{+-}, 2^{++}\right)$ and ``exotic" $\left(J^{P C}=0^{+-}, 1^{++}, 2^{+-}\right)$ C-parities, which are the strange analogue of…
We propose that the search of the $B\to D^{*}_{sJ}M$ decays, $M=D$, $\pi$ and $K$, can discriminate the different theoretical postulations for the nature of the recently observed $D^{*}_{sJ}$ mesons. The ratio of the branching ratios…
The discovery of the $D^\ast_{s0}(2317)$ and $D_{s1}(2460)$ resonances in the charmed-strange meson spectra revealed that formerly successful constituent quark models lose predictability in the vicinity of two-meson thresholds. The…
Masses of the low lying four quark states in the hidden charm sector ($cq\bar c \bar q; q\in u,d$) are calculated within the framework of a non-relativistic quark model. The four body system is considered as two two-body systems such as…
In this work, we tentatively identify the $P_{cs}(4338)$ as the $\bar{D}\Xi_c$ molecular state, and distinguish the isospins of the current operators to explore the $\bar{D}\Xi_c$, $\bar{D}\Lambda_c$, $\bar{D}_s\Xi_c$, $\bar{D}_s\Lambda_c$,…
Motivated by the recent discovery of the first hidden charm pentaquark state with strangeness $P_{cs}(4459)$ by the LHCb Collaboration, we study the likely existence of a three-body $\Sigma_{c}\bar{D}\bar{K}$ bound state, which shares the…
We perform a theoretical study on the spectrum of the low-lying hidden-bottom ($q\bar{q}b\bar{b}$ with $q=$ $u$, $d$ and $s$) and double-bottom ($q\bar{q}bb$) tetraquark states within a nonrelativistic quark model, in which the…
We estimate the masses of the 1^{--} heavy four-quark and molecule states by combining exponential Laplace (LSR) and finite energy (FESR) sum rules known perturbatively to lowest order (LO) in alpha_s but including non-perturbative terms up…
In the present work, we construct the color-singlet-color-singlet type four-quark currents to investigate the $D_s\bar{D}_{s1}$ and $D_s^*\bar{D}_{s0}^*$ tetraquark molecular states with the $J^{PC}=1^{--}$ and $1^{-+}$ via the QCD sum…