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Related papers: Proton Spin Decomposition via QCD Sum Rules

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In this paper, we use momentum sum rule to compute the fractions of momentum carried by quarks and gluons in a self-similarity based model of proton. Comparison of the results with the prediction of QCD asymptotics is also made.

High Energy Physics - Phenomenology · Physics 2015-06-15 Akbari Jahan , D K Choudhury

We present preliminary results on the proton spin structure function in full QCD. The measurement has been done using 4 flavours of staggered fermions and an improved definition of the lattice topological charge density.

High Energy Physics - Lattice · Physics 2009-09-25 B. Alles , G. Boyd , M. D'Elia , A. Di Giacomo

We study the $Q^2$ variation of the first moment of the nucleon's spin-dependent structure function $G_1$. As $Q^2 \rightarrow 0$ the moment is determined by the low energy theorem for Compton scattering. In the deep-inelastic region the…

High Energy Physics - Phenomenology · Physics 2009-10-22 Xiangdong Ji , Peter Unrau

The deuteron disintegration process with the emission of fast proton in the vicinity of the kinematical boundary of the reaction, when Feynman variable $x\to 2$, is studied. The consideration is fulfilled in the framework of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. A. Braun , V. V. Vechernin

One of the challenges of hadronic physics is to fully understand the structure of the proton. In particular, there is nowadays a great interest in the decomposition of its total angular momentum into orbital angular momentum and intrinsic…

High Energy Physics - Phenomenology · Physics 2019-07-16 D. A. Amor-Quiroz , M. Burkardt , C. Lorcé

I discuss the scope and naturalness of the proton mass decomposition (or sum rule) published in PRL74, 1071 (1995) and answer a few criticisms that appeared recently in the literature, focusing particularly on its interpretation and the…

High Energy Physics - Phenomenology · Physics 2021-03-09 Xiangdong Ji

We propose a unified new approach to describe polarized and unpolarized quark distributions in the proton based on the gauge-gravity correspondence, light-front holography, and the generalized Veneziano model. We find that the…

High Energy Physics - Phenomenology · Physics 2020-03-02 Tianbo Liu , Raza Sabbir Sufian , Guy F. de Téramond , Hans Günter Dosch , Stanley J. Brodsky , Alexandre Deur

The structure of the proton remains a significant challenge within the field of Quantum Chromodynamics, with the origin of its spin and mass still lacking a satisfactory explanation. In this study, we utilize the gravitational form factor…

High Energy Physics - Phenomenology · Physics 2023-09-22 Wei Kou , Xurong Chen

The longitudinal double spin asymmetries $A_1^p$ and the spin dependent structure function of the proton $g_1^p$ were extracted from COMPASS data in the region of low Bjorken scaling variable $x$ and low photon virtuality $Q^2$. The data…

High Energy Physics - Experiment · Physics 2019-08-13 A. S. Nunes

Similarities between nuclear structure study with many-body theory approach and nucleon structure calculations with lattice QCD are pointed out. We will give an example of how to obtain the connected sea partons from a combination of the…

High Energy Physics - Phenomenology · Physics 2015-06-19 Keh-Fei Liu

We investigate the angular momentum decomposition with a quantum electrodynamics example to clarify the proton spin decomposition debates. We adopt the light-front formalism where the parton model is well defined. We prove that the sum of…

High Energy Physics - Phenomenology · Physics 2015-01-09 Tianbo Liu , Bo-Qiang Ma

The proton spin crisis remains an unsolved problem in physics. In this paper we find that due to the confinement of partons inside the hadron the angular momentum sum rule in QCD is violated. Hence we find that the non-vanishing angular…

High Energy Physics - Phenomenology · Physics 2018-05-31 Gouranga C Nayak

We investigate the spin structure of the $1^{--}$ and $1^{++}$ charmonium states near the critical temperature using QCD sum rules. To this end, we compute the contribution of the dimension-4 twist-2 gluon operator to the two-point function…

High Energy Physics - Phenomenology · Physics 2025-04-23 HyungJoo Kim

Proton spin problem is given a new perspective with the proposition that spin is a topological invariant represented by a de Rham 3-period. The idea is developed generalizing Finkelstein-Rubinstein theory for Skyrmions/kinks to topological…

General Physics · Physics 2016-12-19 S C Tiwari

Motivated by recent work on three-point QCD sum rules in heavy quark physics, we use the simple quantum mechanical models to study the basic issue of duality in three-point sum rules. We show that while in all of these models the duality in…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. Blok , M. Lublinsky

The generalized Gerasimov-Drell-Hearn (GDH) sum rule is known to be very sensitive to QCD radiative and power corrections. We improve the previously developed QCD-inspired model for the $Q^2$-dependence of the GDH sum rule. We take into…

High Energy Physics - Phenomenology · Physics 2010-10-27 Roman Pasechnik , Jacques Soffer , Oleg Teryaev

We treat the mass of a proton as the total static energy which can be separated into two parts that come from the contribution of quarks and gluons respectively. We adopt the essential of the bag model of hadron to discuss the structure of…

High Energy Physics - Phenomenology · Physics 2010-01-09 Z. G. Tan , L. Y. Huang , C. B. Yang

The use of weak decays to determine proton spin structure is examined in view of possible violations of the Bjorken and Gottfried Sum rules, flavor symmetry breaking and flavor asymmetry in the sea. The use of the neutron decay is found to…

High Energy Physics - Phenomenology · Physics 2009-10-28 Harry J. Lipkin

We study $pp$ scattering at high energies and moderately large momentum transfer using a QCD--based model in which the proton is viewed as being composed of a quark and a diquark. This model leads to spin asymmetries which are neither small…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. V. Goloskokov

We have measured the spin structure functions g2p and g2d and the virtual photon asymmetries A2p and A2d over the kinematic range 0.02 < x < 0.8 and 1.0 < Q^2 < 30(GeV/c)^2 by scattering 38.8 GeV longitudinally polarized electrons from…

High Energy Physics - Experiment · Physics 2008-11-26 E155 Collaboration , P. L. Anthony , R. G. Arnold