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Related papers: Instantons and Single Spin Asymmetries

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The contribution of the quark-quark and quark-gluon interaction induced by instantons to the valence quark and proton spin-dependent structure functions $g_1(x,Q^2)$ is estimated within the instanton liquid model for QCD vacuum. It is…

High Energy Physics - Phenomenology · Physics 2009-10-30 N. I. Kochelev

We calculate the contribution arising from nonperturbative quark-gluon chromomagnetic interaction to the high energy total quark-quark cross section and to gluon distributions in nucleon. The estimation obtained within the instanton model…

High Energy Physics - Phenomenology · Physics 2014-11-20 Nikolai Kochelev

Experimental data on transverse single-spin asymmetry, hyperon polarization and vector meson alignment in h+h, h+A and A+A-collisions have been analyzed. A new mechanism for the origin of single spin effects is proposed, which takes into…

High Energy Physics - Phenomenology · Physics 2007-11-05 V. V. Abramov

QCD instantons generate non-perturbative spin- and flavor- dependent forces between quarks. We review the results of a series of studies on instanton-induced correlations in hadrons. We first present some evidence for instanton-mediated…

High Energy Physics - Phenomenology · Physics 2009-11-10 Pietro Faccioli

We estimate the contribution of nonperturbative quark-gluon chromomagnetic interaction to the high energy elastic proton-proton cross section at large momentum transfer. It is shown that this contribution is very large in the accessible…

High Energy Physics - Phenomenology · Physics 2014-03-05 Nikolai Kochelev , Nikolai Korchagin

Transverse single-spin asymmetries in inclusive deep inelastic lepton-nucleon scattering can be generated through multiphoton exchange between the leptonic and the hadronic part of the process. Here we consider the two-photon exchange, and…

High Energy Physics - Phenomenology · Physics 2015-06-11 A. Metz , D. Pitonyak , A. Schaefer , M. Schlegel , W. Vogelsang , J. Zhou

Different mechanisms have been proposed to account for the spin-dependent interaction between quarks in ground-state hadrons. The first mechanism is the chromomagnetic interaction arising from one-gluon exchange, a second mechanism is an…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. B. Lichtenberg

We discuss the spontaneous breakdown of chiral symmetry in Quantum Chromodynamics by considering gluonic instanton configurations in the partition function. It is shown that in order to obtain nontrivial fermionic correlators in a two…

High Energy Physics - Theory · Physics 2009-10-31 H. R. Christiansen

The spin effects at high energies and momenta transferred $|t|>1 GeV^2$ are analysed for quark-photon scattering. The energy independence of the ratio of spin-flip and spin-non-flip amplitudes in the same $\alpha_s$ order of QCD is…

High Energy Physics - Phenomenology · Physics 2011-08-17 S. V. Goloskokov , O. A. Listopadov

We perform a study of the non-perturbative dynamics of the light-quark sector of QCD, based on some recent results of lattice simulations with chiral fermions. We analyze some correlators that are designed to probe the Dirac structure of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Pietro Faccioli , Thomas A. DeGrand

The transverse single-spin asymmetry A_N observed in high energy proton-proton collisions p^\uparrow p \to pi X has been found to increase with the momentum fraction x_F of the pion up to the largest measured x_F \sim 0.8, where A_N \simeq…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Jarvinen

In this review we will concentrate on the nonperturbative effects in the properties of hadrons made from the light-heavy and heavy-heavy quarks in the framework of Instanton Liquid Model (ILM) of QCD vacuum. We briefly discuss the main…

High Energy Physics - Phenomenology · Physics 2022-01-26 M. Musakhanov , U. Yakhshiev

The Sivers mechanism for the single-spin asymmetry in unpolarized lepton scattering from a transversely polarized nucleon is driven by the orbital angular momentum carried by its quark and gluon constituents, combined with QCD final-state…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. J. Brodsky , S. Gardner

The single-spin asymmetry of unpolarized leptons scattering deep-inelastically off transversely polarized nucleons is discussed. This observable is generated by a two-photon exchange between lepton and nucleon. In a partonic description of…

High Energy Physics - Phenomenology · Physics 2022-03-02 Marc Schlegel

We calculate the production cross-section and the transverse single-spin asymmetry for pion in $p^{\uparrow}+p\to \pi^0 + X$. Our computation is based on existence of the instanton induced effective quark-gluon and quark-gluon-pion…

High Energy Physics - Phenomenology · Physics 2021-02-24 N. Korchagin , N. Kochelev , Pengming Zhang

We show that the instanton-induced inelastic processes, leading to multi-gluon production in in high-energy parton-parton scattering, are considerably enhanced over the quasi-elastic ones, by a factor of 100. The basic instanton-induced…

High Energy Physics - Phenomenology · Physics 2009-10-31 Maciek A. Nowak , Edward V. Shuryak , Ismail Zahed

We discuss a nonperturbative mechanism for one-spin asymmetries in inclusive hadron production. The main role in generation of this asymmetry belongs to the orbital angular momentum of quark-antiquark cloud in internal structure of…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. M. Troshin , N. E. Tyurin

It is shown how the single spin asymmetry observed in inclusive pion production is related, in the helicity basis, to the imaginary part of the product of two different distribution amplitudes, rather than to the usual quark and gluon…

High Energy Physics - Phenomenology · Physics 2009-10-28 Mauro Anselmino , M. E. Boglione , F. Murgia

We present an exact nonperturbative flow equation for the average action for quarks which incorporates the effects of gluon fluctuations. With suitable truncations this allows one to compute effective multiquark interactions in dependence…

High Energy Physics - Phenomenology · Physics 2009-10-28 Christof Wetterich

We investigate the relevance of the instanton-induced determinantal 't Hooft interaction to the eta-nucleon coupling within the framework of a three-flavor linear sigma model in the OZI-rule-respecting basis. Instantons, in combination with…

Nuclear Theory · Physics 2009-09-25 Mauro Napsuciale , Andreas Wirzba , Mariana Kirchbach