Related papers: Nucleon strangeness and spin crisis?
The hyperfine interactions of the constituent quark model provide a natural explanation for many nucleon properties, including the Delta-N splitting, the charge radius of the neutron, and the observation that the proton's quark distribution…
We study effects of the strange quark mass and of the QCD coupling constant in the MIT bag model of quark matter with lowest order quark-gluon interactions on the rapid rotation of strange stars. The influence of rotation on global…
We report on recent lattice QCD calculations of the strangeness magnetic moment of the nucleon and the nucleon electromagnetic form factors, when we allow the electromagnetic current to connect to quark loops as well as to the valence…
I introduce a gauge invariant decomposition of the nucleon spin into quark helicity, quark orbital, and gluon contributions. The total quark (and hence the quark orbital) contribution is shown to be measurable through virtual Compton…
The nucleon-nucleon potential is analysed using the 1/N_c expansion of QCD. The NN potential is shown to have an expansion in 1/N_c^2, and the strengths of the leading order central, spin-orbit, tensor, and quadratic spin-orbit forces…
A remarkably successful program of parity-violating electron scattering experiments is providing new insight into the structure of the nucleon. Measurement of the vector form factors enables a definitive study of potential strange…
Analyses of the three valence-quark bound-state problem in relativistic quantum field theory predict that the nucleon may be understood primarily as a Borromean bound-state, in which binding arises mainly from two separate effects. One…
The strange quark contribution to the vector and axial form factors of the nucleon has been determined for momentum transfers in the range $0.45<Q^2<1.0$ GeV$^2$. The results are obtained via a combined analysis of forward-scattering,…
The leading non-zero electric moment of the nucleon strange-quark vector current is the mean square strangeness radius, $<r_s^2>$. We evaluate the lightest OZI-allowed contribution to $<r_s^2>$, arising from the kaon cloud, using dispersion…
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…
A general three quark bound state satisfying the Pauli principle, and conserving angular momentum and isospin, is used to investigate the spin structure of nucleons at high $x$. It is shown if {$F_{1n}/F_{1p}$$\to$1/4}, then both $A_{1p}$…
In recent decades, the spin and transverse momentum of quarks and gluons were found to play integral roles in the structure of the nucleon. Simultaneously, the onset of gluon saturation in hadrons and nuclei at high energies was predicted…
We study the operator description of the gluon spin contribution ($\Gamma$) to the nucleon's spin as it is measured in deep inelastic processes. $\Gamma$ can be related to the forward matrix element of a local gluon operator in $A^+=0$…
Since the report of the SAMPLE Collaboration suggesting the strange-quark contribution to nucleon magnetic moments, G_M^s(0), may be greater than zero, numerous models have appeared supporting positive values for G_M^s(0). In this paper the…
The fact that strange sea quarks are abundant in the nucleons, but with zero net strangeness, is of great importance for understanding the nature of matter condensed by the strong interaction, particularly in the context of the ``gigantic…
We discuss few, apparently different, but actually tightly related problems: a)Strangeness in the nucleon; b) B --> eta' decays; c)Intrinsic charm in the proton spin problem. We argue that all these problems have a common origin and related…
We present results for the strangeness contribution to the nucleon, <N|ss|N>, and to the spin of the nucleon, Delta s. By combining several variance reduction techniques for all-to-all propagators we are able to obtain gains in terms of…
The leading chiral contributions to the quark and gluon components of the proton spin are calculated using heavy-baryon chiral perturbation theory. Similar calculations are done for the moments of the generalized parton distributions…
A systematic analysis of data on strangeness and pion production in nucleon-nucleon and central nucleus-nucleus collisions is presented. It is shown that at all collision energies the pion/baryon and strangeness/pion ratios indicate…
The strangeness degrees of freedom in the parton structure of the nucleon are explored in the global analysis framework, using the new CTEQ6.5 implementation of the general mass perturbative QCD formalism of Collins. We systematically…