Related papers: Gauge invariance and gluon poles for direct photon…
We consider the direct photon production in two hadron collision with one of the hadrons being transversely polarized. By using the contour gauge for gluon fields, we find that there are new twist-$3$ terms present in the hadron tensor of…
We discuss the role of gluon poles and the gauge invariance for the hadron tensors of Drell-Yan and direct photon production processes with the transversely polarized hadron.
We report on recent work concerning the phenomenology of initial-state parton-kt effects in direct-photon production and related processes in hadron collisions. After a brief summary of a kt-smearing model, we present a study of recent…
An impact of nonperturbatively-treated soft gluon modes on the value of anomalous magnetic moment of muon $a_\mu$ is studied within the mean-field approach to QCD vacuum and hadronization. It is shown that radial excitations of vector…
We argue that through the Wilson lines, gauge invariance has as an effect that the hard functions in weighted spin-asymmetries in hadronic scattering processes are given by gluonic pole cross sections, rather than the usual partonic cross…
We study the cross section for the photoproduction reaction gamma N -> h X in fixed-target scattering at COMPASS, where the hadron h is produced at large transverse momentum. We investigate the role played by higher-order QCD corrections to…
We consider QCD corrections to Higgs boson production through gluon-gluon fusion in hadron collisions. We compute the effects of soft-gluon emission to all orders. We present numerical results at the Tevatron and the LHC.
We consider spin asymmetries for prompt photon production in collisions of longitudinally polarized hadrons. This reaction will be a key tool at the BNL-RHIC pp collider for determining the gluon spin density in a polarized proton. We study…
We discuss the phenomenology of initial-state parton-kt broadening in direct-photon production and related processes in hadron collisions. After a brief summary of the theoretical basis for a Gaussian-smearing approach, we present a…
Initial- and final-state interactions from gluon-exchange, normally neglected in the parton model have a profound effect in QCD hard-scattering reactions, leading to leading-twist single-spin asymmetries, diffractive deep inelastic…
Direct photon production in hadronic collisions provides a handle on the gluon PDF by means of the QCD Compton scattering process. In this work we revisit the impact of direct photon production on a global PDF analysis, motivated by the…
We analyze the capability of prompt photon production in pp and pp(bar) collisions to constrain the gluon distribution of the proton, considering data from fixed-target experiments as well as collider measurements. Combined fits are…
We present comparisons of high-pT photon and pion production in hadronic interactions with expectations from next-to-leading order perturbative QCD (NLO pQCD). We also comment on phenomenological models of kT smearing (which approximate…
We address the problem of decomposing graphs in perturbative QCD into terms associated with particular regions. Motivated by asking how to incorporate next-to-leading order (NLO) QCD corrections in parton-shower algorithms, we require that:…
The gauge invariant two-point correlator for the gluon field strength tensor is analysed by means of the QCD sum rule method. To this end, we make use of a relation of this correlator to a two-point function for a quark-gluon hybrid in the…
Inclusive production of a quarkonium $\eta_{c,b}$ in hadron collisions at low transverse momentum can be used to extract various Transverse-Momentum-Dependent(TMD) gluon distributions of hadrons, provided the TMD factorization for the…
The accurate description of the internal structure of hadrons is a very challenging task. In order to compare the predictions with the highly-accurate experimental data, it is necessary to control any possible source of theoretical…
The spectrum of partons in a QCD jet becomes independent of the primary energy in the low momentum limit. This follows within the perturbative QCD from the colour coherence in soft gluon branching. Remarkably, the hadrons follow such…
We present a study of inclusive direct-photon and pion production in hadronic interactions, focusing on a comparison of the ratio of gamma/pi0 yields with expectations from next-to-leading order perturbative QCD (NLO pQCD). We also examine…
We consider the factorization properties of on-shell QCD amplitudes with massive partons in the limit when all kinematical invariants are large compared to the parton mass and discuss the structure of their infrared singularities. The…