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Related papers: Single-spin asymmetries at two loops

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Transverse single-spin asymmetries (SSA) in inclusive reactions are now considered to be directly related to the transverse momentum $k_{T}$ of the fundamental partons involved in the process. Several possible leading-twist QCD mechanisms…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ivan Schmidt , Jacques Soffer

The transverse single-spin asymmetry for $\rho^0$ production in semi-inclusive deep inelastic scattering was recently reported by the COMPASS Collaboration. Using the Sivers functions extracted from pion and kaon productions, we perform a…

High Energy Physics - Phenomenology · Physics 2025-06-27 Yongjie Deng , Tianbo Liu , Ya-jin Zhou

Predictions for the transverse single spin asymmetry (SSA), A_N, are given for the inclusive processes l p(transv. pol.) --> h X and l p(transv. pol.) --> jet + X, which could be measured in operating or future experiments. These estimates…

High Energy Physics - Phenomenology · Physics 2010-04-06 M. Anselmino , M. Boglione , U. D'Alesio , S. Melis , F. Murgia , A. Prokudin

We study single-spin asymmetries in semi-inclusive deep inelastic scattering with transversely polarized target. Based on the QCD factorization approach, we consider Sivers and Collins contributions to the asymmetries. We fit simple…

High Energy Physics - Phenomenology · Physics 2010-04-06 Werner Vogelsang , Feng Yuan

We present a new analysis for the single-transverse spin asymmetry (SSA) for the inclusive pion and kaon productions in the proton-proton collisions measured at RHIC. The framework we use is the collinear factorization in which SSA appears…

High Energy Physics - Phenomenology · Physics 2015-05-20 Koichi Kanazawa , Yuji Koike

The observed results for the azimuthal single spin asymmetries (SSAs) of the proton, measured in the semi-inclusive deep inelastic scattering (SIDIS), can be explained by the final-state interaction (FSI) from the gluon exchange between the…

High Energy Physics - Phenomenology · Physics 2015-05-20 Narinder Kumar , Harleen Dahiya

A new method is suggested for the extraction of $u$-quark and $d$-quark transversity distributions, using single spin asymmetry (SSA) data in semi-inclusive deep inelastic scattering (SIDIS) processes, where they couple to the Collins or…

High Energy Physics - Phenomenology · Physics 2021-07-26 Mauro Anselmino , Raj Kishore , Asmita Mukherjee

Two factorization approaches have been proposed for single transverse spin asymmetries. One is the collinear factorization, another is the transverse-momentum-dependent factorization. They have been previously derived in a formal way by…

High Energy Physics - Phenomenology · Physics 2014-11-18 H. G. Cao , J. P. Ma , H. Z. Sang

Recent studies have shown that two widely-used mechanisms for single-transverse-spin asymmetries based on either twist-three contributions or on transverse-momentum-dependent (Sivers) parton distributions become identical in a kinematical…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yuji Koike , Werner Vogelsang , Feng Yuan

We study weighted azimuthal single spin asymmetries in hadron-hadron scattering using the diagrammatic approach at leading order and assuming factorization. The effects of the intrinsic transverse momenta of the partons are taken into…

High Energy Physics - Phenomenology · Physics 2009-11-11 A. Bacchetta , C. J. Bomhof , P. J. Mulders , F. Pijlman

Generation of T-odd single spin asymmetries (SSA) by the various ingredients of QCD factorization is discussed. The possible use of SSA in studies of Generalized Parton Distribution (GPD) at HERA with the polarized lepton beam is suggested.…

High Energy Physics - Phenomenology · Physics 2008-11-26 O. V. Teryaev

Establishing the twist-3 formalsim for the single transverse spin asymmetry, we present a complete single-spin-dependent cross section for SIDIS, $ep^\uparrow\to e\pi X$, associated with the twist-3 distribution for the transversely…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hisato Eguchi , Yuji Koike , Kazuhiro Tanaka

Single transverse-spin asymmetries have been studied intensively both in experiment and theory. Theoretically, two factorization approaches have been proposed. One is by using transverse-momentum-dependent factorization and the asymmetry…

High Energy Physics - Phenomenology · Physics 2014-11-18 J. P. Ma , H. Z. Sang

We study the longitudinal-transverse double-spin asymmetry with a $\cos\phi_S$ modulation in semi-inclusive deep inelastic scattering for charged and neutral pions production. We consider the particular case in which the transverse momentum…

High Energy Physics - Phenomenology · Physics 2016-10-31 Xiaoyu Wang , Wenjuan Mao , Zhun Lu

We analyze single-spin asymmetries (SSAs) in the leptoproduction of transversely polarized $\Lambda$ hyperons within the collinear twist-3 formalism. We calculate both the distribution and fragmentation terms in two different gauges…

High Energy Physics - Phenomenology · Physics 2015-05-20 K. Kanazawa , A. Metz , D. Pitonyak , M. Schlegel

We consider a general formalism, previously developed to describe single spin asymmetries (SSA) in inclusive particle production at moderately large $p_T$ in hadron-hadron high-energy processes. In this approach SSA can originate from non…

High Energy Physics - Phenomenology · Physics 2016-09-06 M. Anselmino , M. Boglione , F. Murgia

We analyze the single transverse-spin asymmetry (SSAs) for inclusive hadron production in the $pp$ collision at RHIC based on the twist-3 mechanism in QCD. As an origin of SSAs, we take into account of all kinds of pole contributions…

High Energy Physics - Phenomenology · Physics 2014-11-21 Koichi Kanazawa , Yuji Koike

We suggest inclusive hadron production in ultra-peripheral proton-nucleus collisions (UPCs) $p^\uparrow A \to h AX$ as a new channel to investigate single spin asymmetries (SSAs), in particular, to test the assumed dominance of the…

High Energy Physics - Phenomenology · Physics 2018-12-05 Sanjin Benić , Yoshitaka Hatta

Some estimates for the transverse Single Spin Asymmetry, A_N, in the inclusive processes l p(transv. pol.) --> h X, given in a previous paper, are expanded and compared with new experimental data. The predictions are based on the Sivers…

High Energy Physics - Phenomenology · Physics 2014-04-28 M. Anselmino , M. Boglione , U. D'Alesio , S. Melis , F. Murgia , A. Prokudin

We compute the twist-three fragmentation contribution to the transverse single spin asymmetry (SSA) in light hadron production $p^\uparrow p\to hX$ and $p^\uparrow A\to hX$ including the gluon saturation effect in the unpolarized…

High Energy Physics - Phenomenology · Physics 2017-01-18 Yoshitaka Hatta , Bo-Wen Xiao , Shinsuke Yoshida , Feng Yuan