Related papers: Narrow width pentaquarks
We present an exact calculation of $S$ and $P$ wave $QQ\bar n\bar n$ states using different standard nonrelativistic quark--quark potentials. We explore in detail the charm and bottom sectors looking for bound states that could be measured…
It is pointed out that the previously suggested interpretation of the hidden-charm pentaquarks $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$ as molecular bound states of $\Sigma_c \bar D$ and $\Sigma_c \bar D^*$ baryon-meson pairs gives rise to…
Hidden-charm pentaquark states with double strangeness, $P_{css}$, have been predicted within the framework of unitary coupled-channel dynamics. In this work, we theoretically investigate the potential to observe these states in the decays…
A large data set of proton-nucleus collisions at sqrt(s) =41.6 GeV has been searched for Theta+ and Xi(1862) pentaquark candidates. In 2x10**8 inelastic events we find no evidence for narrow signals (sigma=5 MeV/c**2) in the Theta+ --> pK0s…
We present a very general argument that the analogue of a heavy pentaquark (a state with the quantum numbers of a baryon combined with an additional light quark and a heavy antiquark) must exist as a particle stable under strong…
Several recent experiments have reported evidence for a narrow feature in the K(+)-neutron system, an apparent resonant state ~ 100 MeV above threshold and with a width < 25 MeV. This state has been labelled as Theta(+) (previously as…
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),…
The results of searches for the strange pentaquark states, Theta(1540)+, Xi(1860)-- and Xi(1860)0 in data recorded by the BABAR experiment are presented. We search for these three states inclusively in 123.4 fb^-1 of e+ e- annihilation data…
We study the hadronic molecular structure of hidden heavy pentaquarks - new exotic states composed of charmed/bottom baryons and $D(D^*)/B(B^*)$ mesons. Based on the observation of three pentaquark candidates $P_c^+(4312)$, $P_c^+(4440)$,…
A search for a manifestly exotic S=-2 baryon state decaying to Xi- pi-, and its neutral partner decaying to Xi- pi+, has been performed using 220 pb^(-1) of pp= collisions at sqrt(s)=1.96 TeV collected by the Collider Detector at Fermilab.…
It is shown that the decay amplitude for the Jaffe-Wilczek type pentaquarks is not suppressed by chiral symmetry. On the other hand, pentaquarks of positive or negative parity built up of an antiquark and two chirally different diquarks in…
In this paper, we investigate the hidden-charm pentaquarks as $\bar{D}^{(\ast)}\Lambda_{\rm c}$ and $\bar{D}^{(\ast)}\Sigma^{(\ast)}_{\rm c}$ molecules coupled to the five-quark states. Furthermore, we extend our calculations to the…
If Jaffe and Wilczek's diquark picture for $\Theta_5$ pentaquark is correct, there should also exist a $SU_F$(3) pentaquark octet and singlet with no orbital excitation between the diquark pair, hence $J^P={1/2}^-$. These states are lighter…
This paper presents the results of inclusive searches for the strange pentaquark states $\Theta^+(1540)$, $\Xi_5^{--}(1860)$ and $\Xi_5(1860)^{0}$ as well as the anti-charm pentaquark state $\Theta_c(3099)^{0}$ in a dataset of 123.4…
A systematic lowering in mass of strangeness ambiguous $pK^0_S$ peaks relative to the $nK^+$ is noted. We discuss how measurement of $\gamma p\to \Theta^+ K^0_S\to p K^0_S K^0_S \to p\pi^+\pi^-\pi^+\pi^-$ in association with $\gamma p\to…
In previous papers we developed the light front formulation for Hamiltonians and wave functions (WFs) for mesons and baryons, with both confinement and chiral symmetry breaking. For baryons limited to the lowest Fock component with three…
Within the collective quantization scheme for chiral solitons we discuss states in higher dimensional representations of flavor SU(3) and their relation to radially excited states in the octet. We also consider states which do not have…
The LHCb collaboration have recently updated their analysis of the resonant $J/\psi p$ mass spectrum in the decay $\Lambda_b^0 \to J/\psi p K^-$, making use of their combined Run 1 and Run 2 data. In the updated analysis, three narrow…
We embark on systematic explorations of the behaviour of tetraquark mesons (colour-singlet bound states of two quarks and two antiquarks) in the (idealized) limit of a large number $N_c$ of colour degrees of freedom of quantum…
We presents a systematic analysis of the fall-apart decays for the $1S$, $1P$, and $2S$-wave fully-strange tetraquark states. It shows that most of the fully-strange tetraquark states have a relatively narrow fall-apart decay width of…