Related papers: Pentaquarks and Radially Excited Baryons
In the framework of the nonrelativistic QCD and a quark-diquark model of baryons we have obtained the fragmentation functions for heavy quark to split into spin-1/2 and spin-3/2 double heavy baryons. It was predicted the production rates as…
Evidences for new baryon states with mass >1.8 GeV were obtained in the experiments of the SPHINX Collaboration in studying hyperon-kaon mass spectra in several proton diffractive reactions. The main result of these experiments is the…
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…
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 study possible multiquark contributions to the charm baryon spectrum by considering higher order Fock space components. For this purpose we perform two different calculations. In a first approach we do a coupled-channel calculation of…
The excitation energy spectra of heavy baryons consisting of a heavy quark and two light quarks are investigated by using diquark models in order to examine the nature of the diquark as a constituent of single heavy baryons. We consider two…
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…
Recent results from H1, ZEUS, HERMES and HERA-B on searches for exotic baryons in ep collisions, eD scattering and pA scattering at HERA are reviewed. Evidence for the production of the strange pentaquark Theta^+ and of a narrow…
A possibility of the construction of a periodic table for the excited baryon spectrum is shown in the frame of a relativistic chiral quark model based on selection rules derived from the one-pion exchange mechanism. It is shown that all the…
We investigate two exclusive reactions with a Theta+ pentaquark in the final state: electroproduction of a K meson on the nucleon, and K+ scattering on a neutron target producing a lepton pair. These reactions offer unique opportunities to…
Baryons containing two heavy quarks are treated in the Born-Oppenheimer approximation. Schr\"odinger equation for two center Coulomb plus harmonic oscillator potential is solved by the method of ethalon equation at large intercenter…
Hadron spectroscopy is an important tool towards the study of internal quark dynamics in a composite system. The present article focuses on the study of resonance spectra of strange baryons with S=-2, -3. The non-relativistic approach…
I discuss several topics in chiral perturbation theory - in particular, I recall pecularities of the chiral expansion in the baryon sector.
We present a comprehensive study of the spectra and radiative decays of the triply heavy baryons $\Omega_{ccc}$ and $\Omega_{bbb}$ within a quark-diquark framework using a relativistic screened potential model. The analysis is carried out…
The chiral quark model gives a reasonably good description of many low-energy observables by incorporating the effective degrees carried by the constituent quarks and Goldstone bosons. We calculate the decuplet to octet transition magnetic…
We suggest a new point of view according to which baryon resonances can be understood as collective excitations about intrinsic one-quark excitations in a mean field of definite symmetry. This approach is justified in the limit of large…
We give a survey of recent development and applications of the chiral quark soliton model (also called the Nambu-Jona-Lasinio soliton model) with $N_f$=2 and $N_f$=3 quark flavors for the structure of baryons. The model is an effective…
We report on a recent chiral extrapolation, based on an SU(3) framework, of octet baryon masses calculated in 2+1-flavour lattice QCD. Here we further clarify the form of the extrapolation, the estimation of the infinite-volume limit, the…
We study the radiative decays of the decuplet $(3/2 \to 1/2 \gamma)$ using Heavy Baryon Chiral Perturbation Theory (HBChPT). We emphasize the problems faced by the interacting spin 3/2 field theory. We argue that, to lowest order in the…
Evidences and hints, both from the theoretical and experimental side, of exotic baryon resonances with B=S, have been with us for the last thirty years. The poor status of the general acceptance of these Z* resonances is partly due to the…