Related papers: Next-to-leading order vs. quark off-shellness and …
We pursue a phenomenological study of higher twist effects in high energy processes by taking into account the off-shellness (virtuality) of partons bound in the nucleon. The effect of parton off-shellness in deep inelastic ep->eX…
I shall present a rather pedagogical discussion of the transversity distributions in the quark-parton model and, in particular, the role of perturbative QCD corrections. Among the topics I shall discuss are: LO and NLO evolution, the Soffer…
We calculate the next-to-leading order perturbative QCD corrections to the transverse momentum weighted single transverse spin asymmetry in Drell-Yan lepton pair production in hadronic collisions. We identify the splitting function relevant…
We study higher twist corrections to the perturbative QCD cross sections for ep deep inelastic scattering and the Drell-Yan lepton pair production in pp collision. The corrections arise due to the initial state interaction of the active…
In this paper we study the cross section at leading order in $1/Q$ for polarized Drell-Yan scattering at measured lepton-pair transverse momentum $Q_T$. We find that for a hadron with spin $1/2$ the quark content at leading order is…
We compute cross sections for the Drell-Yan process in N--N collisions at next-to-leading order in $\alpha_s$. The mass, rapidity, transverse momentum, and angular dependence of these cross sections are presented. An estimate of higher…
We present the nuclear transverse momentum broadening for Drell-Yan lepton pair production in p+A collisions at next-to-leading order (NLO) in powers of strong coupling constant $\alpha_s$. We verify that the transverse momentum weighted…
We check numerically if Soffer's inequality for quark distributions is preserved by next-to-leading order QCD evolution. Assuming that the inequality is saturated at a low hadronic scale we estimate the maximal transverse double spin…
We examine the quark-induced Drell-Yan process at next-to-leading power (NLP) in Soft-Collinear Effective Theory. Using an approach with no explicit soft or collinear modes, we discuss the factorization of the differential cross section in…
We calculate the perturbative $T$-odd contributions to the lepton angular distribution in the Drell-Yan process. Using collinear factorization, we work at the first order in QCD perturbation theory where these contributions appear, ${\cal…
At a next-to-leading order calculation, the initial-state energy loss of the quark is investigated by means of the Drell-Yan experimental data including the new E906 measurements. Furthermore, the incoming gluon energy loss effect embedded…
We present comprehensive analysis of the angular structure of the Drell-Yan process at different rapidity and kinematical ranges using data of the ATLAS, LHCb, and CMS Collaborations at CERN LHC. From theory side we discuss next-to-leading…
The Drell-Yan process is studied in the framework of TMD factorization in the Sudakov region $s\gg Q^2\gg q_\perp^2$ corresponding to recent LHC experiments with $Q^2$ of order of mass of Z-boson and transverse momentum of DY pair $\sim$…
The Drell-Yan process provides important information on the internal structure of hadrons including transverse momentum dependent parton distribution functions (TMDs). In this work we present calculations for all leading twist structure…
We carry out next-to-leading order (NLO) parton model calculations for the standard hard ``QCD'' processes in the massless Schwinger model. The asymptotic expansion of the exact result for the deep inelastic cross section is used to infer…
We investigate Drell-Yan pair production in a QCD inspired model, which takes into account all relevant hard processes up to $O(\alpha_s)$. To address the known shortfalls of such a fixed order calculation we introduce phenomenological…
In this contribution I discuss transverse momentum dependent quark distributions and their operator structure. Some of the experimental signatures, in particular in Drell-Yan scattering, are given.
A set of evolution equations for correlators of densities of quark and gluons is considered. Approximate solutions is obtained in frames of gluon and quark dominance. A new formulation of the cross sections of Drell-Yan process is…
We present a first attempt at a global fit of unpolarized quark transverse momentum dependent distribution and fragmentation functions from available data on semi-inclusive deep-inelastic scattering, Drell-Yan and $Z$ boson production…
Within the framework of a high-twist approach, we show the first complete next-to-leading order calculation of transverse momentum broadening in semi-inclusive deeply inelastic $e+A$ scattering and Drell-Yan dilepton production in $p+A$…