相关论文: Narrow width pentaquarks

We analyse the decay $\Theta_s(1/2^+)\to NK$ in a non-relativistic Fock space description using three and five constituent quarks for the nucleon and the pentaquark, respectively. Following Jaffe and Wilczek \cite{jw}, we assume that…

We propose a collective stringlike model of pentaquarks with the geometry of an equilateral tetrahedron in which the four quarks are located at the four corners and the antiquark in its center. The nonplanar equilibrium configuration is a…

We investigate the decay modes of pentaquark baryons for both the antidecuplet and the octet states, which were recently claimed by Close and Dudek to be potentially narrow due to a hidden selection rule. We discuss how ideal mixing between…

The pentaquark state recently discovered has been discussed based on various quark model calculations. Odd parity for the state can not be ruled out theoretically because contributions related to non-trivial color structures have not been…

The experimental evidence for pentaquarks, both old an new, is discussed. Constraints due to $K^+N$ scattering data from previous decades is first reviewed, followed by experiments with positive evidence and those with null results.…

In the framework of the color-magnetic interaction, we have systematically studied the mass splittings of the possible hidden-charm pentaquarks $qqqc\bar{c}$ ($q=u,d,s$) where the three light quarks are in a color-octet state. We find that…

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…

We analyse the width of the $\theta(\frac12^+)$ pentaquark assuming that it is a bound state of two extended spin-zero $ud$-diquarks and the $\bar s$ antiquark (the Jaffe-Wilczek scenario). The width obtained when the size parameters of the…

We study the multiquark hadrons in large $N$ QCD under the 't-Hooft limit, extending Witten's picture of the baryons. We explore the decay widths of tetraquarks, pentaquarks and dibaryons. Based on the decay behaviors, we point out in the…

Evidence for a narrow baryon state at 1528 +- 2.6(stat) +- 2.1(syst) MeV is presented in quasi-real photoproduction on a deuterium target through the decay channel p,K0 to p,pi+,pi-. The statistical significance of the peak in the p,K0…

Pentaquark baryons $\Theta^{+}$ and $\Xi^{--}$ are studied in the dual gravity theory of QCD in which simple mass formulae of pentaquarks are derived in the Maldacena prototype model for supersymmetric QCD and a more realistic model for…

The 1/N expansion for exotic baryons is developed, and applied to the masses, meson couplings and decay widths. Masses and widths of the 27 and 35 pentaquark states in the same tower as the Theta+ are related by spin-flavor symmetry. The 27…

In a diquark-diquark-antiquark picture of the pentaquark we study the decay $\Theta \rightarrow K^{+} n$ within the framework of QCD sum rules. After evaluation of the relevant three-point function, we extract the coupling $g_{\Theta nK}$…

We review and discuss the experimental evidence on predicted baryonic states made by 4 quarks and one antiquark, called pentaquarks. Theoretical and experimental advances in the last few years led to the observation of pentaquark candidates…

Assuming the two diquark structure for the pentaquark state as advocated in the Jaffe-Wilczek model, we study the strong decays of light and heavy parity-even pentaquark states using the light-front quark model in conjunction with the…

Scrutinizing the scattering of ordinary mesons in the limiting case of the number of colour degrees of freedom $N_{\rm c}$ of quantum chromodynamics approaching infinity, we formulate Feynman-diagram selection criteria and from these deduce…

Assuming that the recently observed $\Theta^+$ and $\Xi^{--}$ are members of an anti-decuplet of SU(3), decays to ground state baryons and mesons are calculated using an effective Lagrangian which incorporates chiral and SU(3) symmetry. We…

Recently LHCb reported the discovery of five extremely narrow excited $\Omega_c$ baryons decaying into $\Xi_c^+ K^-$. We interpret these baryons as bound states of a $c$-quark and a $P$-wave $ss$-diquark. For such a system there are exactly…

We discuss the magnetic moments of the recently discovered exotic baryons Theta(+) and Xi(--) and their multiplet partners in the framework of a naive additive quark model. These baryons are set up as pentaquark states where four quarks and…

We used an effective Lagrangian approach to investigate the production of the anticharmed pentaquark state $P_{\bar{c}s}^{(*)-}$ with the minimal quark content $\bar{c}sudd$ in the $\Lambda_b^0$ decay and its decay into the $\Lambda…