Related papers: Instanton contribution to the Sivers function
We discuss the role of instantons in the spectroscopy of ordinary and exotic hadrons as well as in high energy reactions. We argue that the instanton induced flavor- and spin-dependent quark-quark and quark-gluon interactions can explain…
The instanton contribution to the quark distribution functions in the nucleon is estimated. It is shown, that taking into account the instanton induced interaction between quarks allows to explain the anomalous violation of the Ellis-Jaffe…
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…
The nonperturbative effects in the quark form factor are considered in the Wilson loop formalism. The properties of the Wilson loops with cusp singularities are studied taking into account the perturbative and nonperturbative contributions,…
The instanton vacuum picture is used to study hadronic matrix elements of the twist-3 (dimension-4, spin-1) QCD operators measuring the quark spin density and spin-orbit correlations. The QCD operators are converted to effective operators…
The nonperturbative effects in the high-energy processes involving strongly interacting particles are studied within the instanton liquid model of the QCD vacuum (ILM) by using the Wilson integral framework. The detailed analysis of…
We develop a formalism to evaluate the Sivers function. The approach is well suited for calculations which use constituent quark models to describe the structure of the nucleon. A non-relativistic reduction of the scheme is performed and…
Instantons are the natural mechanism in non-perturbative QCD to remove helicity from valence quarks and transfer it to gluons and quark-antiquark pairs. To understand the extent to which instantons explain the so-called "spin crisis" in the…
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…
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…
A formalism is presented to evaluate the Sivers function in constituent quark models. A non-relativistic reduction of the scheme is performed and applied to the Isgur-Karl model. The results obtained are consistent with a sizable Sivers…
We calculate the Sivers function of $\bar{u}$ and $\bar{d}$ quarks using the overlap representation within the light-cone formalism. The light-cone wave functions of the proton is obtained in terms of the $|\bar{q} q B\rangle$ Fock states…
It is by now well understood that spin asymmetry in deep inelastic scattering (DIS) can appear if two things are both present: (i) a chirality flip of the struck quark; (ii) a nonzero T-odd phase due to its final state interaction. So far…
The $k_\perp$-moment of a quark's Sivers function is known to be related to the corresponding twist-three quark-gluon correlation function $T_{q,F}(x, x)$. The two functions have been extracted from data for single-spin asymmetries in…
A new mechanism for single spin asymmetries in strong interaction is proposed. It is based on instanton-induced nonperturbative chromomagnetic quark-gluon interaction. We estimate the contribution of this interaction to single spin…
Chiral quark model with a broken-U(3) flavor symmetry can be interpreted as the effective theory of the instanton-dominated non-perturbative QCD. This naturally suggests the possibility of a negative singlet/octet coupling ratio, which has…
The same light-front wave functions of the proton are involved in both the anomalous magnetic moment of the nucleon and the Sivers function. Using the diquark model, we derive a simple relation between the anomalous magnetic moment and the…
We perform a calculation of the Sivers function in a spectator model of the nucleon, with scalar and axial-vector diquarks. We make use of gluon rescattering to produce the nontrivial phases necessary to generate the Sivers function. The…
Nonperturbative nolocal structure of QCD vacuum is well described by instanton model. Specific helicity and flavor structure of zero modes of quarks in instanton field allows simultaneously to explain some important features of low- and…
It is shown that specific spin-flavour properties of the nonperturbative interaction between quarks induced by instantons allow us to explain the peculiarities of the OZI rule violation in $N \bar N$ annihilation. New experiments to test…