Polarized Gluon Distribution Delta g(x) in the Proton

Abstract

We study the polarized gluon distribution $\Delta g(x)$ in a longitudinally polarized proton. We argue that the distribution can be calculated approximately from the quark color currents found in simple quark models. The first result from the MIT bag model as well as the non-relativistic quark model shows that $\Delta g(x)$ is positive at all $x$. If this feature holds in QCD, it imposes a strong constraint on phenomenological fits to experimental data. The total gluon helicity $\Delta G$ from the bag model is about $0.3\hslash$ at the scale of 1 GeV, considerably smaller than previous theoretical expectations.

6 pages, 3 figures

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Cited by in corpus (10)

• The Spin Structure of the Nucleon
• Extraction of Spin-Dependent Parton Densities and Their Uncertainties
• Physics of Gluon Helicity Contribution to Proton Spin
• Gluon Helicity Delta G from a Universality Class of Operators on a Lattice
• Phenomenological analysis of the nucleon spin contents and their scale dependence
• The Spin Budget of the Proton at NNLO and Beyond
• The spin of the proton in chiral effective field theory
• Polarized gluon distribution in the proton from holographic light-front QCD
• Exploring the polarization of gluons in the nucleon
• Angular Momentum in Non-Relativistic QED and Photon Contribution to Spin of Hydrogen Atom