English
Related papers

Related papers: Quark Sivers Function at Small-$x$: Leading contri…

200 papers

The Sivers function is extracted from HERMES data on single spin asymmetries in semi-inclusive deeply inelastic scattering. Our analysis use a simple Gaussian model for the distribution of transverse parton momenta, together with the flavor…

High Energy Physics - Phenomenology · Physics 2009-11-11 J. C. Collins , A. V. Efremov , K. Goeke , S. Menzel , A. Metz , P. Schweitzer

The Sivers function, an asymmetric transverse-momentum distribution of the quarks in a transversely polarized nucleon, is calculated in the MIT bag model. The bag quark wave functions contain both $S$-wave and $P$-wave components, and their…

High Energy Physics - Phenomenology · Physics 2015-06-25 Feng Yuan

$\pi$-$N$ $\sigma$ term and proton axial vector matrix elements are calculated including disconnected contributions with a variant wall source method using the Wilson quark action at $\beta=5.7$ in quenched QCD. For the $\sigma$ term, we…

High Energy Physics - Lattice · Physics 2009-10-28 M. Fukugita , Y. Kuramashi , M. Okawa , A. Ukawa

Single-spin asymmetries observed in polarised deep-inelastic scattering are important probes of hadron structure. The Sivers asymmetry provides information about the transverse momentum of the struck quark and can be related to final-state…

High Energy Physics - Lattice · Physics 2025-02-04 K. U. Can , J. A. Crawford , R. Horsley , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

Measurements of single-spin asymmetries for semi-inclusive electro-production of pions and kaons in deep-inelastic scattering with transverse target polarization open a new window on the transverse quark and gluon structure of the nucleon.…

High Energy Physics - Experiment · Physics 2007-05-23 H. E. Jackson

The contribution of a spin-rich $qqq$ force (in conjunction with pairwise $qq$ forces) to the analytical structure of the $qqq$ wave function is worked out in the high momentum regime of QCD where the confining interaction may be ignored,…

High Energy Physics - Phenomenology · Physics 2009-04-21 A. N. Mitra

I study the effect of scalar and spin-orbit absorption potentials, in the production of a nonzero Sivers-like asymmetry in hadron-hadron high energy collisions (Drell-Yan and single spin asymmetries). A basic model is built for the…

High Energy Physics - Phenomenology · Physics 2007-06-21 Andrea Bianconi

Through an impulse approximation analysis of single spin Sivers and Collins asymmetries in the Bjorken limit, the possibility to extract the quark transverse-momentum distributions in the neutron from semi-inclusive deep inelastic electron…

High Energy Physics - Phenomenology · Physics 2013-02-12 Emanuele Pace , Giovanni Salme' , Sergio Scopetta , Alessio Del Dotto

We compute the transverse single spin asymmetry in forward $p^\uparrow p \to hX$ and $p^\uparrow A \to hX$ collisions from the odderon mechanism originally suggested by Kovchegov and Sievert [1]. Working in the hybrid approach of the Color…

High Energy Physics - Phenomenology · Physics 2023-01-04 Sanjin Benić , Davor Horvatić , Abhiram Kaushik , Eric Andreas Vivoda

We investigate the Wigner distributions for $u$ and $d$ quarks in a light-front quark-diquark model of a proton to unravel the spatial and spin structure. The light-front wave functions are modeled from the soft-wall AdS/QCD prediction. We…

High Energy Physics - Phenomenology · Physics 2017-05-09 D. Chakrabarti , T. Maji , C. Mondal , A. Mukherjee

Within the light-quark sector of the standard model, P-odd observables are generated from point-like electroweak processes while A_t- odd observables (neglecting quark mass parameters) come from dynamic spin-orbit correlations within…

High Energy Physics - Phenomenology · Physics 2016-09-06 Dennis Sivers

We study the single spin asymmetry in the back-to-back dijet production in transversely polarized proton-proton collisions. Such an asymmetry is generated by the Sivers functions in the incoming polarized proton. We propose a QCD formalism…

High Energy Physics - Phenomenology · Physics 2022-12-06 Zhong-Bo Kang , Kyle Lee , Ding Yu Shao , John Terry

We report progresses on leading-twist transverse-momentum-dependent (TMD) gluon distributions, calculated in a spectator-model framework for the parent nucleon. We encode in our formalism a fit-based parameterization for the spectator-mass…

High Energy Physics - Phenomenology · Physics 2022-03-11 Alessandro Bacchetta , Francesco Giovanni Celiberto , Marco Radici

A formalism to evaluate the Sivers function, developed for calculations in constituent quark models, is applied to the Isgur-Karl model. A non-vanishing Sivers asymmetry, with opposite signs for the u and d flavor, is found; the Burkardt…

High Energy Physics - Phenomenology · Physics 2017-08-23 S. Scopetta , A. Courtoy , F. Fratini , V. Vento

We show how some parton distribution functions related to the transverse spin of nucleons can be extracted point by point from combinations of proton and deuteron observables. In particular, we present a determination of the valence and sea…

High Energy Physics - Phenomenology · Physics 2017-02-06 Anna Martin , Franco Bradamante , Vincenzo Barone

We study the process dependence of the Sivers function by considering the impact of color-gauge invariant initial and final state interactions on transverse spin asymmetries in proton-proton reactions within the framework of the transverse…

High Energy Physics - Phenomenology · Physics 2011-10-27 Umberto D'Alesio , Leonard Gamberg , Zhong-Bo Kang , Francesco Murgia , Cristian Pisano

We introduce a new model of near-forward elastic proton-(anti)proton scattering at high energy based on the modern formulation of Pomeron and Odderon in terms of Wilson lines and generalized TMDs (GTMDs). We compute the helicity-dependent…

High Energy Physics - Phenomenology · Physics 2020-06-24 Yoshikazu Hagiwara , Yoshitaka Hatta , Roman Pasechnik , Jian Zhou

We propose a one-point charge-correlator (OPCC) probe of the Sivers effect in back-to-back deep-inelastic scattering. This measurement uses only the signs and directions of charged tracks, with no calorimetric or particle-identification…

High Energy Physics - Phenomenology · Physics 2026-05-18 Haotian Cao , Xiaohui Liu , Frank Petriello

So far the analyses of the polarized structure functions of the proton and neutron have been limited to the evaluation of their integrals and comparing them to the prediction of the static quark model of the nucleon. We extended our…

High Energy Physics - Phenomenology · Physics 2018-10-30 B. Povh , M. Rosina

Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicity included. $\Lambda_b$ ,…

High Energy Physics - Phenomenology · Physics 2009-10-31 Gary R. Goldstein