Related papers: Is There a Third Companion of Lambda and Sigma0?
We review recent progress in our understanding of the nucleon excitation spectrum. Thanks to dedicated efforts at facilities such as ELSA, MAMI and Jefferson Lab, several new nucleon resonances have been discovered, and evidence for…
Recent experimental data on space-like and time-like form factors of the nucleon are analyzed in terms of a two-component model with a quark-like intrinsic three-quark structure and quark-antiquark pairs.
Our current knowledge of the baryon--baryon interaction suggests that the dineutron $(n,n)$ and its strange analogue $(n,\Lambda)$ are unstable. In contrast, the situation is more favorable for the strange three-body system $(n,n,\Lambda)$,…
We note that the same mathematical results apply to problems involving quasispin and isospin, but the problems per se are different. In the quasispin case, one deals with a system of identical fermions (e.g. neutrons) and address the…
The ground state masses and binding energies of the nucleon, $\Lambda^0$, $\Lambda^+_c$, $\Lambda^0_b$ are studied within a constituent quark QCD-inspired light-front model. The light-front Faddeev equations for the $Qqq$ composite spin 1/2…
Diagonal and transition magnetic moments of the negative parity, spin-1/2 heavy baryons are studied in framework of the light cone QCD sum rules. By constructing the sum rules for different Lorentz structures, the unwanted contributions…
The electric quadrupole and magnetic octupole moments of the light decuplet baryons are calculated in the framework of the light cone QCD sum rules. The obtained non-vanishing values for the electric quadrupole and magnetic octupole moments…
If quark matter is energetically favored over nuclear matter at zero temperature and pressure then it has long been expected to take the form of strange quark matter (SQM), with comparable amounts of $u$, $d$, $s$ quarks. The possibility of…
The comparison of magnetic moments of neutron and proton reveals three possible stationary states of a nucleon: s-, p- and o-nucleon with different configurations and presumably different masses. Two of these nucleons may exist as the small…
Only photons are needed to explain the masses of the pi(0), eta, Lambda, Sigma(0), Xi(0), Omega(-), Lambda(c,+), Sigma(c,0), Xi(c,0), and Omega(c,0) mesons and baryons. Only neutrinos are needed to explain the mass of the pi(+-) mesons.…
The electromagnetic properties of the SU(3)-flavor baryon decuplet are examined within a lattice simulation of quenched QCD. Electric charge radii, magnetic moments, and magnetic radii are extracted from the E0 and M1 form factors.…
In the chiral $SU(15)$ gauge theory presented here, the quarks and leptons are bound states ("prebaryons") of massless preons. The Standard Model charges of the preons imply 3 generations of quarks and leptons, plus some vectorlike fermions…
A menage a trois is very different from an ordinary family. Similarly, exotic hadrons with both qq and qbar q pairs have important color-space correlations that are completely absent in ordinary mesons and baryons. The presence of both…
In this paper, axion models supplemented by leptoquarks and diquarks are systematically analyzed. Turning on some couplings to and among these latter states permits to unify the Peccei-Quinn symmetry with baryon (B) and lepton (L) numbers,…
Magnetic moments of baryons composed of light and strange quarks are computed for the first time through the only parameter of the model -- string tension $\sigma$. Resulting theoretical values differ from the experimental ones typically by…
In recent years there has been a rapidly growing body of experimental evidence for existence of exotic, multiquark hadrons, i.e. mesons which contain additional quarks, beyond the usual quark-antiquark pair and baryons which consist of more…
In a particle theory model whose most readily discovered new particle is the $\sim 1$TeV bilepton resonance in same-sign leptons, currently being sought at CERN's LHC, there exist three quarks ${\cal D, S, T}$ which will be bound by QCD…
The general character of 4-quark (mesonic) and strange 6-quark (baryonic) quark systems is very briefly reviewed a la Jaffe, i.e. in the MIT bag, and so far still possibly viable candidates are indicated. Concentration is on S=-2 systems.…
The recent measurement by CDF M(Sigma_b)-M(Lambda_b)=192 MeV is in striking agreement with our theoretical prediction M(Sigma_b)-M(Lambda_b) = 194 MeV. In addition, the measured splitting M(Sigma_b*)-M(Sigma_b) = 21 MeV agrees well with the…
The three-dimensional spatial structure of hadrons is encoded in their form factors. Via appropriate Fourier transform, the latter describe how charge, energy, linear and angular momentum, but also pressure are distributed inside these…