Related papers: The Roper resonance and kin
We measured angular distributions of differential cross section, beam analyzing power, and recoil polarization for neutral pion electroproduction at Q^2 = 1.0 (GeV/c)^2 in 10 bins of W across the Delta resonance. A total of 16 independent…
We report the predictions for the 3q core contributions to the electroexcitation of the resonances Delta(1232)3/2+, N(1440)1/2+, N(1520)3/2-, N(1535)1/2-, and N(1675)5/2- on the proton obtained in the light-front relativistic quark model…
This talk focuses on a recent work aiming at determining the composition of certain $N^*$ and $\Delta$ resonances, i.e. whether they are compact states formed directly by quarks and gluons, or composite generated from the meson-baryon…
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…
The low-lying bottomonium-like tetraquarks $b\bar{b}q\bar{q}$ $(q=u,\,d,\,s)$ with spin-parity $J^P=0^+$, $1^+$ and $2^+$, and isospin $I=0,\,1$ or $\frac{1}{2}$, are systematically investigated within the theoretical framework of real- and…
A classification of the $IJ^{PC}=00^{++}$ mesons is performed on the basis of the K-matrix analysis of meson spectra in the reactions: (i) GAMS data on $\pi p\to \pi^0\pi^0 n$, $\eta\eta n$, $\eta\eta' n$; (ii) Crystal Barrel data on $p\bar…
The constituent quark model can explain the strong selectivity of the $N\eta$ decay branching ratios of the nucleon resonances if the fine structure interaction between the constituent quarks is described in terms of Goldstone boson…
In a resonance model the reactions pi N -> Y K and pi Delta -> Y K are studied. For the reactions pi N -> Lambda K and pi Delta -> Lambda K, the resonances N(1650)(J^P=1/2^-), N(1710)(1/2^+) and N(1720)(3/2^+) are included as intermediate…
The identification of problematic meson states as the members of the quark model $q\bar{q}$ nonets by using a hadronic resonance spectrum is discussed. The results favor the currently adopted $q\bar{q}$ assignments for the axial-vector,…
It was found that the isoscalar-scalar and isovector-scalar mesons play significant roles in nuclear matter physics. However, the underlying structures of these resonances are not yet well understood. We construct a three-flavor baryonic…
We have performed a 3-D Monte Carlo simulation of a system composed of two identical light quarks ($qq$) and two identical antiquarks ($\bar Q\bar Q$) and determined whether it is energetically more favorable to form a tetraquark or two…
We analyze mesons in constant magnetic fields ($B$) within a non-relativistic constituent quark model. Our quark model contains a harmonic oscillator type confining potential, and we perturbatively treat short range correlations to account…
In order to describe Lambda(1405) as a resonance in the baryon-meson scattering, we have investigated q^3-q qbar scattering system with the flavor-singlet q^3 (0s)^2(0p) state (the Lambda^1 pole). The scattering is treated by the quark…
Experimentally observed excited strange charmed mesons $D_{s0}^*(2317)^{\pm}$, $D_{s1}(2460)^{\pm}$, $D_{s1}(2536)^{\pm}$, $D_{s2}^*(2573)^{\pm}$, $D_{s1}^*(2700)^{\pm}$, $D_{s1}^*(2860)^{\pm}$, $D_{s3}^*(2860)^{\pm}$, and…
We utilize various {\em ab initio} approaches to search for a low-lying resonance in the four-neutron ($4n$) system using the JISP16 realistic $NN$ interaction. Our most accurate prediction is obtained using a $J$-matrix extension of the…
We address $q q \bar Q\bar Q$ exotic tetraquark bound states and resonances with a fully unitarized and microscopic quark model. We propose a triple string flip-flop potential, inspired in lattice QCD tetraquarks static potentials and…
In these notes, while focusing on the meson-nucleon vertices, we give a derivation of the nucleon-nucleon 9NN) potentials from meson-exchange between quarks. To establish such a relation the quark-quark-meson (QQM) interactions are properly…
In this work the investigation of hadronic structures with the help of the harmonic quarks is prolonged. The harmonic quark model is good at describing the meson structures and the baryon excitations to resonances, in particular…
The sensitivity of the deuteron form factor to contributions from the excited states of the nucleon is explored using a simple model of the nucleon-nucleon interaction which employs a tower of charged nucleon resonances. The model is…
We discuss the quantum mechanics of coalescence of quark-antiquark pairs into mesons using a non-relativistic quark model. We derive the coalescence probabilities assuming a harmonic oscillator potential and generic Gaussian wave packet…