Related papers: Gluon Distributions and Fits using Dipole Cross-Se…
At small x, the effects of finite transverse momenta of partons inside a hadron become increasingly important, especially in analyses of jets and heavy-quark production. These effects can be systematically accounted for in a formalism based…
We have used QCD and polarized deep-inelastic scattering data to construct x-dependent polarized parton distributions. These flavor dependent distributions evolve under the NLO DGLAP equations, satisfy positivity constraints and agree well…
We present an analysis of the current methods of approximate determination of the gluon density $G(x,Q^2)$ at low-$x$ from the scaling violations of the proton structure function $F_2(x,Q^2)$. The gluon density is obtained from DGLAP…
In the semiclassical approach, inclusive and diffractive quark and gluon distributions are expressed in terms of correlation functions of Wilson loops. Each Wilson loop integrates the colour field strength in the area between the…
Accurate gluon densities at small $x$ are essential for reducing theoretical uncertainties in collider predictions, yet remain one of the least constrained ingredients in global analyses. We report recent advances in the resummation of…
The behavior of the gluon distribution of the proton in the low-$x$, low-$Q^2$ domain of deep inelastic electron-proton scattering (DIS) is being investigated. By considering two-gluon exchange as the dominant interaction in the low-$x$,…
We investigate the recently proposed nonlinear equation for the unintegrated gluon distribution function which includes the subleading effects at small $x$. We obtained numerically the solution to this equation in $(x,k)$ space, and also…
We obtain an approximate analytical form of the gluon distribution using the GLAP equation with a factorization ansatz,and test its validity by comparing it with that of Gluck,Reya and Vogt at low $x$ regime. We also present calculations of…
In this paper we study the gluon distribution functions in nucleons and pions at a low resolution $Q^2$ scale. This is an important issue since parton densities at low $Q^2$ have always been taken as an external input which is adjusted…
It has been argued recently that parton showers based on colour dipoles conflict with collinear factorization and do not lead to the correct DGLAP equation. We show that this conclusion is based on an inappropriate assumption, namely the…
Using momentum sum rule for evolution equations for Double Parton Distribution Functions (DPDFs) in the leading logarithmic approximation, we find that the double gluon distribution function can be uniquely constrained via the single gluon…
We present the gluon distribution functions of pion and kaon in small-$x$ and large-$x$ regions, and compare them with the results obtained from lattice QCD and continuum Schwinger function methods. Whether in the small-$x$ region or the…
We present an analysis of the color-dipole picture (CDP) for determination of the gluon density at low-$x$ which is obtained from the Altarelli-Martinelli equation by expansion at distinct points of expansion. The dipole cross-sections with…
We present very simple non-integral relations between deep inelastic structure functions $F_L$, $F_2$ and the gluon distribution at small $x$ based on perturbative QCD which are useful for the phenomenological analysis of data at low $x$.…
We investigate the implication of uncertainties in the unintegrated gluon distribution for the predictions for central exclusive production of scalars at hadron colliders. We use parameterizations of the kT-unintegrated gluon density…
We present numerical studies of the leading non-linear corrections to the DGLAP evolution equations of parton distribution functions (PDFs) resulting from gluon recombination, which reduce the pace of evolution at small momentum fractions…
We discuss perturbative evolution of the polarized structure function g_1 in the (x,Q^2) plane, with special regard to the small-x region. We determine g_1 in terms of polarized quark and gluon distributions using coefficient functions to…
We present a full evaluation of the deeply virtual Compton scattering (DVCS) cross section in the dipole framework in the small-x region. The result features the $\cos \phi$ and $\cos 2\phi$ azimuthal angular correlations which have been…
As a consequence of QCD factorization theorems, a wide variety of inclusive and exclusive cross sections may be formulated in terms of a universal colour dipole cross section at small $x$. It is well known that for small transverse size…
The low $x$ behaviour of the gluon density $xg(x,\mu^2)$ at scale $\mu^2=2.4$ GeV$^2$ is determined using exclusive $J/\psi$ production data from HERA and LHCb within the framework of collinear factorisation at next-to-leading order (NLO).…