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Related papers: Spin Structure of the Proton

200 papers

The flavor and spin structure for the quark distributions of the $\Lambda$-baryon is studied in a perturbative QCD (pQCD) analysis and in the SU(6) quark-diquark model, and then applied to calculate the $\Lambda$-polarization of…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bo-Qiang Ma , Ivan Schmidt , Jian-Jun Yang

We study the global polarization of spin-$3/2$ hadrons in relativistic heavy ion collisions. We show in particular that the global tensor polarizations of rank two or three for spin-$3/2$ hadrons are sensitive to the local two or three…

High Energy Physics - Phenomenology · Physics 2024-06-07 Zhe Zhang , Ji-peng Lv , Zi-han Yu , Zuo-tang Liang

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

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…

Nuclear Theory · Physics 2026-02-12 De-Xian Wei

In order to obtain polarised parton densities we have made next to leading order QCD fit using experimental data on deep inelastic structure functions on nucleons. This fit is compared with the updated fit to coresponding spin asymmetries.…

High Energy Physics - Phenomenology · Physics 2009-11-07 Jan Bartelski , Stanislaw Tatur

We discuss a few examples of structure functions for polarized, semi-inclusive scattering processes to show the richness of structure. Then we indicate how polarization and particle production can be used to study the quark and gluon…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. J. Mulders

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…

High Energy Physics - Lattice · Physics 2024-10-11 Fangcheng He , Jian Liang , Yi-Bo Yang

We performed a phenomenological fit in order to get quark parton polarized distributions in the nucleon. All data on inclusive and semi-inclusive spin asymmetries measured on nucleon targets were used. We present the results for the flavour…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jan Bartelski , Stanislaw Tatur

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…

High Energy Physics - Phenomenology · Physics 2022-11-23 Chengdong Han , Gang Xie , Rong Wang , Xurong Chen

We present a consistent calculation of the structure functions within a light-front constituent quark model of the nucleon. Relativistic effects and the relevance of the covariance constraints are analyzed for polarized parton…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Faccioli , F. Cano , M. Traini , V. Vento

We have measured the spin-dependent structure function $g_1^p$ in inclusive deep-inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003 < x < 0.7$ and $1 GeV^2 < Q^2 < 60 GeV^2$. A next-to-leading order…

High Energy Physics - Experiment · Physics 2010-01-15 D. Adams

We check the $u$ and $d$ quark contributions to the spin content of the $\Lambda$ by means of the $q\to\Lambda$ fragmentation and find that the $u$ and $d$ quarks of the $\Lambda$ are likely positively polarized. The parton distributions in…

High Energy Physics - Phenomenology · Physics 2011-02-01 Jian-Jun Yang

We present results on the spin carried by quarks and gluons in the nucleon using lattice QCD simulations with physical values of the light, strange and charm quark masses. We also discuss selective results on the x-dependence of parton…

High Energy Physics - Lattice · Physics 2023-01-18 Constantia Alexandrou

We present a quark-parton model to describe polarized and unpolarized nucleon structure functions. The twist-two matrix elements for the QCD evolution analysis of lepton-hadron scattering are calculated within a light-front covariant quark…

High Energy Physics - Phenomenology · Physics 2011-04-15 Marco Traini , Pietro Faccioli , Vicente Vento

The study of two spin asymmetries in hadron-hadron collisions probes the details of fundamental particle interactions in ways infeasible to machines with unpolarized collisions. Within reach is how the proton spin is distributed among its…

High Energy Physics - Phenomenology · Physics 2008-02-03 Glenn A. Ladinsky

We discuss the spin structure of the proton in a light-cone treatment of the chiral quark model. Based on the fact that the quark helicity ($\Delta q$) measured in polarized deep inelastic scattering experiments is actually the quark spin…

High Energy Physics - Phenomenology · Physics 2012-07-03 Xinyu Zhang , Bo-Qiang Ma

We calculate the spin density matrix of the hadron $h$ created via quark fragmentation in the process $e^-e^+ \to q\bar q \to h + X$. In the case of $h=\Lambda$ the experimental data could possibly elucidate the problem of $s$-quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Anselm , M. Anselmino , F. Murgia , M. G. Ryskin

The STAR collaboration at the Relativistic Heavy Ion Collider is using polarized proton beams at sqrt{s} = 200 GeV to study the spin structure of the proton. The first results for the double spin helicity dependence of inclusive jet…

High Energy Physics - Experiment · Physics 2008-11-26 J. Sowinski

We review the present understanding of the spin structure of protons and neutrons, the fundamental building blocks of nuclei collectively known as nucleons. The field of nucleon spin provides a critical window for testing Quantum…

High Energy Physics - Phenomenology · Physics 2026-01-13 A. Deur , S. J. Brodsky , G. F. de Teramond

Understanding the internal spin structure of the nucleon remains a challenge in strong interaction physics. The unique capability of RHIC opened new avenues in studying the internal structure of the proton with unprecedented depth and…

High Energy Physics - Experiment · Physics 2024-04-26 Ting Lin