相关论文: Three quark currents and baryon spin
We analyze the axial-vector form factors of the nucleon-hyperon system in a model with SU(3)$_{\text{flavor}}$ symmetry breaking due to mass dependent quark spin polarizations. This mass dependence is deduced from an analysis of magnetic…
We study the complete set of flavor changing hyperon axial current matrix elements at small momentum transfer. Using partially quenched heavy baryon chiral perturbation theory, we derive the chiral and momentum behavior of the axial and…
Using the unified scheme for describing both quark spin and orbital angular momenta in the chiral quark model developed in the previous work, the magnetic moments of octet and decuplet baryons are calculated. The numerical result shows that…
We investigate the electric form factors and charge radii of the pentaquark baryons within the framework of the chiral quark-soliton model. We consider the rotational $1/N_c$ and linear $m_s$ corrections, assuming isospin symmetry and…
We perform the first Lattice calculation about the charmed hadron spin decomposition using overlap fermions on a 2+1 flavor RBC/UKQCD domain-wall gauge configurations at 0.083 fm with 300 MeV pion mass. It is found that the contributions of…
Magnetic moments of baryons in the ground-state octet and decuplet are calculated in a light-front framework. We investigate the effects of quark mass variation both in the current operator and in the wavefunctions. A simple fit uses single…
The chiral constituent quark model (\chiCQM) with general parameterization (GP) method has been formulated to calculate the quadrupole moments of the spin 3/2^+ decuplet baryons and spin 3/2^+ \to 1/2^+ transitions. The implications of such…
The baryon axial vector current is computed in a combined formalism in $1/N_c$ and chiral corrections. Flavor $SU(3)$ symmetry breaking is accounted for in two ways: Implicitly through the integrals occurring in the one-loop graphs and…
Using generalized Sehgal equations for magnetic moments of baryon octet and taking into account $\Sigma^{0}-\Lambda$ mixing and two particle corrections to independent quark contributions we obtain very good fit using experimental values…
We investigate the spin contribution to light baryon ground states in three inequivalent large-$N$ limits: 't Hooft, QCD antisymmetric and QCD symmetric. Our framework is a constituent quark model with a relativistic Hamiltonian containing…
Lattice calculations of the proton spin components is reviewed. The lattice results of the quark spin from the axial-vector current matrix element at $\sim 0.3- 0.4$ is smaller than those from the constituent quark models. This is largely…
The part of the proton spin $\Sigma$ carried by $u, d, s$ quarks is calculated in the framework of the QCD sum rules in the external fields. The operators up to dimension 9 are accounted. An important contribution comes from the operator of…
Following the first clear evidence of the presence of intrinsic charm contribution in the proton, the axial-vector charges of the light and charmed baryons are investigated in the framework of $SU(4)$ chiral constituent quark model after…
The magnetic moments of $J^P=\frac{3}{2}^+$ decuplet baryons have been calculated in the chiral constituent quark model ($\chi$CQM) with explicit results for the contribution coming from the valence quark polarizations, sea quark…
In this contribution, we present the unquenched quark model as an extension of the constituent quark model that includes the effects of sea quarks via a $^{3}P_{0}$ quark-antiquark pair-creation mechanism. Particular attention is paid to…
The axial-vector form factors and axial-vector constants of the baryon decuplet are investigated within a pion mean-field approach, which is also known as the chiral quark-soliton model. Given an axial-vector current with a specified…
We calculate chiral corrections to the octet axial currents through ${\cal O}(p^3)$ using baryon chiral perturbation theory (BCPT). The relativistic BCPT framework allows one to sum an infinite series of recoil corrections at a given order…
The QCD sum rule method is formulated for the strangeness +1 pentaquark baryon with isospin I=0 and spin-parity J^P = 3/2^\pm. The spin-3/2 states are considered to be narrower than the spin-1/2 ones, and thus may provide a natural…
An alternate method is described to extract the quark contribution to the spin of the nucleon directly from the first moment of the deuteron structure function, $g^d_1$. It is obtained without recourse to the use of input on the nucleon…
The spin structure of the proton is investigated in the framework of an extended quark potential model which in addition to the conventional $3q$--structure also takes into account $(3q)(q\bar q)$--admixtures in the proton wave function.…