相关论文: Evolution of Gluon Spin in the Nucleon

Evolution of the parton densities at NLO in $\alpha_S$ using $\tilde W^2 = Q^2 (1-z)/z$ instead of the usual $Q^2$ for the scale of the running coupling $\alpha_S$ is investigated. While this renormalisation scale change was originally…

We present the first measurement of the Q^2-dependence of the neutron spin structure function g_2^n at five kinematic points covering 0.57 (GeV/c)^2 <= Q^2 <= 1.34 (GeV/c)^2 at x~0.2. Though the naive quark-parton model predicts g_2=0,…

The proton spin puzzle is a longstanding problem in high-energy nuclear physics: how the proton spin distributes among the spin and orbital angular momenta of the quarks and gluons inside. Two of the unresolved pieces of the puzzle are the…

The strong interaction is not well understood at low energy, or for interactions with low momentum transfer $Q^2$, but one of the clearest insights we have comes from Chiral Perturbation Theory ($\chi$PT). This effective treatment gives…

We study deep-inelastic scattering from polarized nuclei within a covariant framework. A clear connection is established between relativistic and non-relativistic limits, which enables a rigorous derivation of convolution formulae for the…

We present the polarized parton distribution functions from a QCD analysis of the worldwide polarized deep inelastic scattering data, based on the dynamical parton distribution model. All the sea quarks and gluons are dynamically generated…

We have utilized the concept of valon model to calculate the spin structure functions of proton, neutron and deuteron. The valon structure itself is universal and arises from the perturbative dressing of the valence quark in QCD. Our…

In this paper we have solved the nonlinear Gribov-Levin-Ryskin-Mueller-Qiu (GLR-MQ) evolution equation for gluon distribution function G(x,Q^2) and studied the effects of the nonlinear GLR-MQ corrections to the Leading Order (LO)…

We review the theory of polarized deep inelastic scattering in light of the most recent experimental data. We discuss the nucleon spin decomposition and the Bjorken sum rule. The latter is used for extraction of…

We examine the gluon distributions in nuclei in the asymptotic region defined by $Q^2 \to \infty$, $x \to 0$. An analysis using the Double Asymptotic Scaling variables of Ball and Forte is proposed. New scaling relations are predicted which…

It is shown that the amplitude for the scattering of a heavy quarkonium system from a nucleon near threshold is completely determined by the fraction of angular momentum, as well as linear momentum, carried by gluons in the nucleon. A form…

Spin polarization provides a novel probe of the rotational properties of the quark-gluon plasma formed in relativistic heavy-ion collisions. This work investigates the equation of state, particularly its transport and thermodynamic…

The theoretical framework for a next-to-leading order QCD analysis of the spin-dependent parton densities Delta f^{gamma}(x,Q^2) of the longitudinally polarized photon and of its structure function g_1^{gamma}(x,Q^2) is reviewed in some…

The evolution of polarized quark distribution functions is taken into account the gluon emission and absorption, quark pair production and annihilation processes and treated by a statistical method which provides quark distribution…

We have studied the spin dynamics of a high-mobility two-dimensional electron system in a GaAs/Al_{0.3}Ga_{0.7}As single quantum well by time-resolved Faraday rotation and time-resolved Kerr rotation in dependence on the initial degree of…

We propose a new mechanism of generating spin polarization in heavy-ion collisions dominated by nucleon degree of freedom. By incorporating the spin change in nucleon-nucleon scatterings based on the phase shift data together with the…

The nucleon spin structure is studied at COMPASS via the measurement of the spin dependent properties of deep inelastic muon-deuteron scattering. Both inclusive and semi-inclusive observables are investigated, with the emphasis put on the…

We propose an evolution equation for unintegrated gluon densities that is valid for large values of the QCD coupling constant $\bar{\alpha} _s$. Our approach is based on the linear resummation model introduced by Sta\'{s}to. We generalize…

We study polarized inelastic electron-nucleon scattering at low momentum transfer in the Witten-Sakai-Sugimoto model of holographic QCD, focusing on resonance production contributions to the nucleon spin structure functions. Our analysis…

The total gluon helicity in a polarized proton, measurable in high-energy scattering, is shown to be the large momentum limit of a gauge-invariant but non-local, frame-dependent gluon spin $\vec{E}\times \vec{A}_\perp$ in QCD. This opens a…