Related papers: Quark Spin and Orbital Angular Momentum in the Bar…
The chiral nonanalytic behaviour of quark-flavor contributions to the magnetic moments of octet baryons are determined in full, quenched and partially-quenched QCD, using an intuitive and efficient diagrammatic formulation of quenched and…
We determine within lattice QCD, the nucleon spin carried by valence and sea quarks, and gluons. The calculation is performed using an ensemble of gauge configurations with two degenerate light quarks with mass fixed to approximately…
The contributions from the $qqqq\bar q$ components to the magnetic moments of the octet as well as the $\Delta^{++}$ and $\Omega^-$ decuplet baryons are calculated for the configurations that are expected to have the lowest energy if the…
We have used the light-cone formulation of Chiral-Quark Soliton Model to investigate the vector and axial content of octet, decuplet and the hypothetical antidecuplet in the flavor SU(3) symmetry limit. We have extended previous works by…
We investigate the quark spin content of the SU(3) baryon octet, decuplet, antitriplet, and sextet in a pion mean-field approach or the chiral quark-soliton model, considering the $1/N_c$ rotational corrections and SU(3) symmetry breaking…
The relatively small fraction of the spin of the proton carried by its quarks presents a major challenge to our understanding of the strong interaction. Traditional efforts to explore this problem have involved new and imaginative…
In analogy to the Altarelli-Parisi equation for the quark and gluon helicity contributions to the nucleon spin, we derive an evolution equation for the quark and gluon orbital angular momenta. The solution of the combined equations yields…
The orbital angular momenta $L^u$ and $L^d$ of up and down quarks in the proton are estimated as functions of the energy scale as model-independently as possible, on the basis of Ji's angular momentum sum rule. This analysis indicates that…
Magnetic moments of the low lying and charmed spin 1/2^+ and spin 3/2^+ baryons have been calculated in the SU(4) chiral constituent quark model (\chiCQM) by including the contribution from c \bar c fluctuations. Explicit calculations have…
Effect of the quark intrinsic motion on the proton spin structure functions is demonstrated. It is shown, that the covariant version of the quark-parton model taking into account the orbital motion gives the consistent picture of the proton…
Theoretical progress on the formulation and classification of the quark and gluon orbital angular momenta (OAM) is reviewed. Their relation to parton distributions and open questions and puzzles are discussed. We give a status report on the…
We present calculations of the decuplet baryon magnetic moments in the chiral quark model. As input we use parameters obtained in qualitatively accurate fits to the octet baryon magnetic moments studied previously. The values found for the…
New relations between the quark spin-flavor contents of the nucleon and axial weak coupling constants are obtained in the chiral quark model with both SU(3) and U(1)-breaking effects. Using the nonsinglet spin combinations, $\Delta_3$ and…
Several spin and flavor dependent parameters characterizing the strangeness content of the nucleon have been calculated in the chiral constituent quark model with configuration mixing (\chiCQM_{config}) which is known to provide a…
The nucleon spin problem raises experimental and theoretical questions regarding the contribution of the orbital angular momentum of the quarks to the total spin of the nucleon. In this article we examine the commutation relationships of…
The statistical model in combination with detailed balance principle is able to phenomenological calculate and analyze spin and flavor dependent properties like magnetic moments (with effective masses, effective charge, with both effective…
The quark model description of the hyperon nucleon forces, especially the antisymmetric spin-orbit forces, is studied from the spin-flavor SU(6) and the flavor SU(3) symmetry point of view. It is pointed out that the quark exchange…
The status of lattice calculations of the quark spin, the quark orbital angular momentum, the glue angular momentum and glue spin in the nucleon is summarized. The quark spin calculation is recently carried out from the anomalous Ward…
Using the MIT bag model, we study the contribution from the gluon vector potential due to the spectators to the orbital angular momentum of a quark in the bag model. For $\alpha_s = {\cal O}(1)$, this spectator contribution to the quark…
Working within the non relativistic quark model a two parameter fit to the magnetic moments of baryons is presented. The fit has an excellent $\chi^2$. The model is based on taking different flavor groups to describe the different magnetic…