Related papers: The ccbar Pentaquarks by a Quark Model
There are different assumptions on the substructure of the pentaquarks $P_c(4380)$ and $P_c(4450)$, newly founded in $J/\psi N $ invariant mass by the LHCb collaboration, giving consistent mass results with the experimental observations.…
A vector meson exchange model based on effective Lagrangians is used to build the meson--baryon interaction in the charm $+1$, strangeness $-2$ and isospin $0$ sector. The s-wave scattering amplitudes resulting from the unitarization in…
The lattice QCD simulation of $NJ/\psi$ and $N\eta_c$ scattering is performed at $m_\pi\simeq 266~$MeV in channels with all possible $J^P$. This includes $J^P=3/2^\pm$ and $5/2^\pm$ where LHCb discovered $P_c(4380)$ and $P_c(4450)$…
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…
We analyze the $K^-p\to K^+\Xi^-$ and $K^-p\to K^0\Xi^0$ processes in the energy region $1.8<\sqrt{s}<2.8$ GeV within an effective Lagrangian approach. The $\Lambda(1800)$ and $\Sigma(2250)$ resonances, along with the ground states $\Sigma$…
We construct the complete set of positive parity pentaquarks, which correspond in the quark model to {\bar s} q^{Nc+1} states with one unit of orbital angular momentum L=1. In the large Nc limit they fall into the K=1/2 and K=3/2 irreps…
Motivated by the recent discovery of the hidden charm exotic state with strangeness by the BESIII and LHCb Collaborations, we study the $S$ wave strange hidden bottom tetraquark in two kinds of quark models. Both meson-meson and…
In this article, we construct the color singlet-singlet type five-quark currents with the isospins $(I,I_3)=(\frac{1}{2},\frac{1}{2})$ and $(\frac{3}{2},\frac{1}{2})$ unambiguously to explore the $\bar{D}\Sigma_c$, $\bar{D}\Sigma_c^*$,…
We investigate the hidden-charm pentaquarks as superpositions of $\Lambda_c \bar{D}^{(*)}$ and $\Sigma_c^{(*)} \bar{D}^{(*)}$ (isospin $I = 1/2$) meson-baryon channels coupled to a $uudc\bar{c}$ compact core by employing an interaction…
In the paper, we construct eight color singlet-singlet type five-quark currents with distinguished isospins to study the $\bar{D}\Xi^{\prime}$, $\bar{D}\Xi_c^{*}$, $\bar{D}^{*}\Xi_c^{\prime}$ and $\bar{D}^{*}\Xi_c^{*}$ molecular states with…
We investigate three possible pentaquark candidates, one of which contains a single charm quark and the other two contain triple charm quarks in their substructure. To this end we apply QCD sum rule method and take into account both the…
The nature of the three narrow $P_c$ states, i.e., $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$, is under intense discussion since their discovery from the updated analysis by LHCb. In this work we extend our previous coupled-channel approach…
Very recently, the LHCb collaboration has reported the new result about the hidden-charm pentaquarks: $P_c(4312)$ near the $\bar{D}\Sigma_c$ threshold, and $P_c(4440)$ and $P_c(4457)$ near $\bar{D}^*\Sigma_c$ threshold. We study the heavy…
The QCD sum rule method is formulated for the strangeness +1 pentaquark baryon with isospin I=0 and spin-parity J^P = 3/2^\pm. The spin-3/2 states are considered to be narrower than the spin-1/2 ones, and thus may provide a natural…
Predictions for the low-lying excitation spectrum of positive parity pentaquark systems containing one c or b antiquark and four light u,d quarks are obtained in the quark model picture for models with spin-dependent interactions given…
The masses of tetraquark states of all $qc\bar q \bar c$ and $cc\bar c \bar c$ quark configurations are evaluated in a constituent quark model, where the Cornell-like potential and one-gluon exchange spin-spin coupling are employed. All…
We study the spin $\frac12$ hadronic state in quenched lattice QCD to search for a possible $S=+1$ pentaquark resonance. Simulations are carried out on $8^3\times 24$, $10^3\times 24$, $12^3\times 24$ and $16^3\times 24$ lattices at…
The 2015 LHCb discovery of a structure (denoted by $P_c^+$) decaying in $J/\psi \,p$ and conjectured to be a penta-quark state, has triggered a renewed interest in the question of possible existence of multi-quark states not predicted by…
We demonstrate that a five quark state of positive parity with an internal P-wave structure - usually pictured as a composite of an antiquark and two diquarks in a P-wave state - can couple to nucleons and Goldstone particles in a chirally…
We study the $P_{cs}(4459)^0$ recently observed by LHCb using the method of QCD sum rules. Our results support its interpretation as the $\bar D^* \Xi_c$ hadronic molecular state of either $J^P=1/2^-$ or $3/2^-$. Within the hadronic…