Related papers: Understanding penta quark with various quark model…
Dynamical calculations are performed for all isomultiplets of the flavour antidecuplet to which the newly discovered pentaquark $\Theta^+$ belongs. The framework is a constituent quark model where the short-range interaction has a…
$QQ^\prime qq\bar q$ pentaquarks are studied in a potential model, under the hypothesis that they are composite objects of two diquarks and one antiquark. The interaction between two colored objects includes two contributions, one based on…
A narrow pentaquark state, $P_c(4312)^+$, decaying to $J/\psi p$ is discovered with a statistical significance of $7.3\sigma$ in a data sample of ${\Lambda_b^0\to J/\psi p K^-}$ decays which is an order of magnitude larger than that…
Assuming four-quark structure for the $X$ resonances in low-lying region, we calculate their masses using the color-spin interaction. In specific, the hyperfine masses of the color-spin interaction are calculated for the possible states in…
The reaction $\gamma p \to pK^+K^-$ was studied at Jefferson Lab with photon energies from 1.8 to 3.8 GeV using a tagged photon beam. The goal was to search for a $\Theta^{++}$ pentaquark, a narrow doubly charged baryon state having…
We study the mass spectra of hidden-charm pentaquarks having spin $J = {1\over2}/{3\over2}/{5\over2}$ and quark contents $uud c \bar c$. We systematically construct all the relevant local hidden-charm pentaquark currents, and select some of…
The recently discovered tetraquark, $T_{cc}^+$, has quark content $cc\bar{u}\bar{d}$ and a mass that lies just below open charm thresholds. Hence it is reasonable to expect the state to have a significant molecular component. We calculate…
We investigate the pentaquark system $qqqs \bar q$ in a framework of chiral quark model. Two structures, $(qqq)(s\bar{q})$ and $(qqs)(q\bar{q})$, with all possible color, spin, flavor configurations are considered. The calculations show…
I review some selected aspects of the phenomenology of multiquark states discovered in high energy experiments. They have four valence quarks (called tetraquarks) and two of them are found to have five valence quarks (called pentaquarks),…
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…
In this article, we study the magnetic moment of the pentaquark $ \Theta^+(1540)$ as (scalar)diquark-(pseudoscalar)diquark-antiquark state with the QCD sum rules approach in the external electromagnetic field. Due to the special structure…
The LHCb collaboration reported a fully charmed tetraquark state X(6900) in the invariant mass spectrum of $J/\psi$ pairs in 2020. This discovery inspires us to further study the fully heavy pentaquark system. In this work, we investigate…
Motivated by the latest discovery of doubly-charmed tetraquark $T^+_{cc}$ by LHCb collaboration, we have studied the magnetic moments of the possible doubly-heavy pentaquark states with quantum numbers $J^P = 1/2^-$ and $J^P = 3/2^-$ within…
We study spin 1/2 isoscalar and isovector candidates in both parity channels for the recently discovered \Theta^+(1540) pentaquark particle in quenched lattice QCD. Our analysis takes into account all possible uncertainties, such as…
A quark model, which reproduces the ground-state mesons and baryons, i.e., the threshold energies, is applied to the $qqqc\bar c$ configurations, where $q$ is a light quark and~$c$ the charmed quark. In the calculation, several open…
In this talk, multiquarks are studied microscopically in a standard quark model. In pure ground-state pentaquarks the short-range interaction is computed and it is shown to be repulsive, a narrow pentaquark cannot be in the groundstate. As…
The problem of the long life time of the pentaquark $\Theta^+$ is investigated on the basis of the color molecular dynamics simulation. We find that it takes a long time (typically of 50-100 fm/c) for the initial pentaquark-state to…
Claims concerning the possible discovery of the \Theta^+ pentaquark, with minimal quark content uudd\bar{s}, have motivated our comprehensive study into possible pentaquark states using lattice QCD. We review various pentaquark…
We study the recently discovered Theta^+ baryon in the context of the perturbative chiral quark model. The basic configuration of the Theta^+ is set up as a pentaquark bound state, where the single particle wave functions are the ground…
In the article, we investigate the diquark-diquark-antiquark type fully-heavy pentaquark states with the spin-parity $J^P={\frac{1}{2}}^-$ via the QCD sum rules, and obtain the masses $M_{cccc\bar{c}}=7.93\pm 0.15\,\rm{GeV}$ and…