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Related papers: The Parton Orbital Angular Momentum: Status and Pr…

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Applying the connection between the parton Wigner distribution and orbital angular momentum (OAM), we investigate the probe of the gluon OAM in hard scattering processes at the planned electron-ion collider. We show that the single…

High Energy Physics - Phenomenology · Physics 2017-05-17 Xiangdong Ji , Feng Yuan , Yong Zhao

Since the announcement of the proton spin crisis by the European Muon Collaboration there has been considerable progress in unravelling the distribution of spin and orbital angular momentum within the proton. We review the current status of…

High Energy Physics - Phenomenology · Physics 2009-08-03 A. W. Thomas

We revisit the problem of the small Bjorken-$x$ asymptotics of the quark and gluon orbital angular momentum (OAM) distributions in the proton utilizing the revised formalism for small-$x$ helicity evolution derived recently in a paper by…

High Energy Physics - Phenomenology · Physics 2023-07-20 Brandon Manley

Here we study the quark orbital angular momentum of the ground octet baryons employing an extended chiral constituent quark model, within which the baryon wave functions are taken to be superposition of the traditional $qqq$ and the…

High Energy Physics - Phenomenology · Physics 2023-03-01 Jing-Feng Li , Cheng Chen , Gang Li , Chun-Sheng An , Cheng-Rong Deng , Ju-Jun Xie

Using the unified scheme for describing both quark spin and orbital angular momenta in the chiral quark model developed in the previous work, the magnetic moments of octet and decuplet baryons are calculated. The numerical result shows that…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiaotong Song

Quark orbital angular momentum in the proton is evaluated via a Lattice QCD calculation of the second Mellin moment of the twist-3 generalized parton distribution $\widetilde{E}_{2T} $ in the forward limit. The connection between this…

High Energy Physics - Lattice · Physics 2024-06-04 M. Engelhardt , N. Hasan , S. Krieg , S. Liuti , S. Meinel , J. Negele , A. Pochinsky , M. Rodekamp , S. Syritsyn

We introduce gauge-invariant quark and gluon angular momentum distributions after making a generalization of the angular momentum density operators. From the quark angular momentum distribution, we define the gauge-invariant and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Pervez Hoodbhoy , Xiangdong Ji , Wei Lu

Definitions of orbital angular momentum based on Wigner distributions are used as a framework to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar.We find that the…

High Energy Physics - Phenomenology · Physics 2015-06-05 Matthias Burkardt

We investigate the quark angular momentum in a model with the nucleon being a quark and a spectator. Both scalar and axial-vector spectators are included. We perform the calculations in the light-cone formalism where the parton concept is…

High Energy Physics - Phenomenology · Physics 2015-01-16 Tianbo Liu , Bo-Qiang Ma

Analytical and numerical results, for the orbital and spin content carried by different quark flavors in the baryons, are given in the chiral quark model with symmetry breaking. The reduction of the quark spin, due to the spin dilution in…

High Energy Physics - Phenomenology · Physics 2009-10-31 Xiaotong Song

Quark spin and orbital angular momentum in the nucleon are calculated in symmetry-breaking chiral quark model. The results are compared with data and other models.

High Energy Physics - Phenomenology · Physics 2007-05-23 X. Song

The leading order evolution of parton orbital angular momenta is treated in the probabilistic manner. As a result, the splitting probability matrix, while coinciding with the recent explicit calculations, is expressed in the terms of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 O. V. Teryaev

The quantum theory of rotation angles (S. M. Barnett and D. T. Pegg, Phys. Rev. A, 41, 3427-3425 (1990)) is generalised to non-integer values of the orbital angular momentum. This requires the introduction of an additional parameter, the…

Quantum Physics · Physics 2009-11-13 J. B. Goette , S. Franke-Arnold , R. Zambrini , Stephen M. Barnett

We study the covariant version of the quark-parton model, in which the general rules of the angular momentum composition are accurately taken into account. We demonstrate how these rules affect the relativistic interplay between the quark…

High Energy Physics - Phenomenology · Physics 2015-06-23 Petr Zavada

Orbital angular momentum (OAM) is not a Poincar\'e invariant quantity; so, its value is observer dependent. Notwithstanding that, in quantum chromodynamics, a Poincar\'e-invariant theory, OAM is part of every hadron wave function. Using…

High Energy Physics - Phenomenology · Physics 2026-03-17 Y. -Y. Xiao , Z. -N. Xu , Z. -Q. Yao , C. D. Roberts , J. Rodríguez-Quintero

It is known how to access information on quark orbital angular momentum from generalized parton distribution functions, in a certain specified framework. It is intuitively expected, that such information can be accessed also through…

High Energy Physics - Phenomenology · Physics 2017-08-23 H. Avakian , A. V. Efremov , P. Schweitzer , O. V. Teryaev , P. Zavada

Quark orbital angular momentum (OAM) in the proton can be calculated directly given a Wigner function encoding the simultaneous distribution of quark transverse positions and momenta. This distribution can be accessed via proton matrix…

High Energy Physics - Lattice · Physics 2019-01-04 M. Engelhardt , J. Green , N. Hasan , S. Krieg , S. Meinel , J. Negele , A. Pochinsky , S. Syritsyn

Wigner distributions contain combined position and momentum space information of the quark distributions and are related to both generalized parton distributions (GPDs) and transverse momentum dependent parton distributions (TMDs). We…

High Energy Physics - Phenomenology · Physics 2015-06-23 Asmita Mukherjee , Sreeraj Nair , Vikash Kumar Ojha

An unified scheme for describing both spin and orbital motion in symmetry-breaking chiral quark model is suggested. The analytic results of the spin and orbital angular momenta carried by different quark flavors in the nucleon are given.…

High Energy Physics - Phenomenology · Physics 2007-05-23 X. Song

The orbital angular momentum ($L_q$) of the proton is studied by employing the extended constituent quark model. Contributions from different flavors, namely, up, down, strange, and charm quarks in the proton are investigated. Probabilities…

High Energy Physics - Phenomenology · Physics 2019-06-05 C. S. An , B. Saghai