Related papers: Probing the twist-3 multi-gluon correlation functi…
We prove that twist-3 soft-gluon-pole (SGP) cross section for single spin asymmetries is determined by a certain ``primordial'' twist-2 cross section up to kinematic and color factors in the leading order perturbative QCD. This unveils…
We calculated the single spin asymmetry in the inclusive pion production in the fragmentation region of transversely polarized proton-proton collisions. We generated the asymmetry at the level of fragmentation function (Collins effect) by…
We have studied the effects of nonlinear scale evolution of the parton distribution functions to charm production in $pp$ collisions at center-of-mass energies of 5.5, 8.8 and 14 TeV. We find that the differential charm cross section can be…
We study charm production in ultra-relativistic heavy-ion collisions by using the Parton-Hadron-String Dynamics (PHSD) transport approach. The initial charm quarks are produced by the Pythia event generator tuned to fit the transverse…
We present a new analysis of $A_N$ in $p^\uparrow p\to \pi\, X$ within the collinear twist-3 factorization formalism. We incorporate recently derived Lorentz invariance relations into our calculation and focus on input from the kinematical…
We present next-to-leading order QCD corrections for the cross sections for $\ell p^\uparrow\to hX$, $\ell p^\uparrow\to {\mathrm{jet}}X$ with transversely polarized initial protons. These cross sections are known to be power-suppressed in…
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…
To extract information about polarized gluons in the proton, production of charmed hadrons, in particular, \Lambda_c^+ baryon in pp collisions was studied. We calculated the transverse momentum distribution and the pseudo-rapidity…
The spin polarization functions $(\Delta u, ~\Delta d, ~\Delta s)$ for proton are calculated in the chiral quark model ($\chi$QM) with SU(3) symmetry breaking as well as configuration mixing generated by one gluon exchange forces for the…
We find a novel mechanism for generating transverse single-spin asymmetry (SSA) in semi-inclusive deep inelastic scattering, distinct from the known ones which involve the Sivers and Collins functions, or their collinear twist-three…
Transverse polarization in the Hyperon production in the unpolarized deep inelastic scattering and pp collisions is studied in the twist-three approach, considering the contribution from the quark-gluon-antiquark correlation distribution in…
The unintegrated gluon density in the photon is determined, using the Kimber-Martin-Ryskin prescription . In addition, a model of the unintegrated gluon is proposed, based on the saturation model extended to the large-x region. These gluon…
The gluon polarisation in the nucleon was measured using open charm production by scattering 160 GeV/c polarised muons off longitudinally polarised protons or deuterons. The data were taken by the COMPASS collaboration between 2002 and…
We study the scattering of a single parton state with a multi-parton state to derive the complete results of perturbative coefficient functions at leading order, which appear in the collinear factorization for Single transverse-Spin…
We calculate in the framework of the collinear QCD approach the amplitude for exclusive neutrino-production of a pseudoscalar charmed $D$ meson. This process allows to access gluon and both chiral-odd and chiral-even quark generalized…
We investigate the Collins effect in single spin asymmetries (SSAs) of the $p^{\uparrow}p \to \pi X$ process, by taking into account the transverse momentum dependence of the microscopic sub-processes cross sections, with the transverse…
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…
We investigate the transverse polarization of a hyperon produced in the high-energy unpolarized proton-proton collision, $pp\to\Lambda^\uparrow X$, based on the collinear twist-3 factorization formalism. We focus on the contribution from…
Recent results on the production of open charm in electron proton scattering at HERA are reviewed. Results on the fragmentation of charm are presented and compared to the measurements at e+e- colliders. Recent results on the charm…
We prove factorization and gauge invariance of the twist-3 single-spin-dependent cross section in the leading order perturbative QCD, which was missing in the previous literature. We emphasize that the consistency relation from the Ward…