相关论文: Baryonium X(1835)
From the quark confinement idea, we conjecture that the quarks compose colorless particles (uud and udd - the Lee Particles) and then the Lee Particles construct a body center cubic lattice in the vacuum. In terms of the energy band theory,…
We review the current status of determinations of the b-quark mass, m_b. We describe the theoretical tools required for determining m_b, with particular emphasis on effective field theories both in the continuum and on the lattice. We…
We generalize the usual octet, decuplet and exotic antidecuplet and higher baryon multiplets to any number of colours Nc. We show that the multiplets fall into a sequence of bands with O(1/Nc) splittings inside the band and O(1)splittings…
This paper aims to give further evidence for the existence of low mass exotic baryons. Narrow structures in baryonic missing mass or baryonic invariant mass were observed during the last twelve years. Since their evidence is still under…
Assuming that vector and scalar diquarks exist in the Quark-Gluon Plasma near the critical temporature $T_c$, baryons can be produced through the processes of quarks and diquarks forming $({1/2})^+$ baryon states. Ratios of different…
We compute masses of positive parity spin-$1/2$ and $3/2$ baryons composed of $u$, $d$, $s$, $c$ and $b$ quarks in a quark-diaquark picture. The mathematical foundation for this analysis is implemented through a symmetry-preserving…
The recent observation by CDF of Sigma_b^{+-} (uub and ddb) baryons within 2 MeV of the predicted Sigma_b - Lambda_b splitting has provided strong confirmation for the theoretical approach based on modeling the color hyperfine interaction.…
The pentaquarks are exotic baryons formed of four quarks and an antiquarks. Their existence has been discussed in the literature over the last 30 years or more, first in connection with kaon nucleon scattering data. The subject has been…
The ratios between different baryonic species masses are studied. The result is used to tentatively predict some missing baryonic masses, still not experimentally observed.
Predictions of unknown heavy baryon masses based on an expansion in $1/m_Q$, $1/N_c$ and $SU(3)$ breaking are updated to take into account a recent measurement of the $\Sigma_c^*$ mass. Values are given for the two remaining unknown charm…
Hypernuclei $ ^4_Y He$, $ ^4_Y H$, $ ^4_{YY} He$, $ ^4_{YY} H$, where $Y=\Lambda$, $\Sigma_0$, $\Sigma_+$, $\Sigma_-$, A=4 are considered using the relativistic twelve-quark equations in the framework of the dispersion relation technique.…
Starting from an effective Hamiltonian modelling a baryon made of $N$ identical quarks in the large-$N$ approach of QCD, we obtain analytical formulas allowing to estimate the contributions of multiquark interactions to the baryon mass. The…
The baryon form factor of charged pions arises since isospin symmetry is broken with unequal up and down quark masses, $m_d>m_u$, as well as electromagnetic effects. We obtain estimates for this basic property in two phenomenological ways:…
The mass spectra of doubly heavy baryons are systematically calculated in the framework of QCD sum rules. With a tentative heavy-diquark--light-quark configuration, the interpolating currents representing the doubly heavy baryons are…
The finite size of doubly heavy diquark gives a positive correction to the masses of baryons calculated in the local diquark approximation. We evaluate this correction for the basic states of doubly charmed baryons to give quite accurate…
General features of spontaneous baryogenesis are studied. The relation between the time derivative of the (pseudo)goldstone field and the baryonic chemical potential is revisited. It is shown that this relation essentially depends upon the…
The recent constraints on the cosmological parameters put from the observations of the WMAP satellite limit the cosmic baryon fraction in a range that is larger than, and marginally consistent with, what is measured in galaxy clusters. This…
The relativistic four-quark equations are found in the framework of coupled-channel formalism. The dynamical mixing of the meson-meson states with the four-quark states is considered. The approximate solutions of these equations using the…
The accidental baryonic symmetry is expected to be broken and required from the observed matter-antimatter asymmetry. The neutron-antineutron oscillating system is the hallmark of $\Delta \mathcal{B} = 2$ models which have the benefits of…
Predictions for the electromagnetic form factors of the Lambda$, Sigma and Xi hyperons are presented. The numerical calculations are performed within the framework of the fully relativistic constituent-quark model developed by the Bonn…