Related papers: Unified QCD evolution equations for quarks and glu…
I examine the solution of the BFKL equation with NLO corrections relevant for deep inelastic scattering. Particular emphasis is placed on the part played by the running of the coupling. It is shown that the solution factorizes into a part…
A new representation for the two-to-four gluon vertex arising in the context of unitarity corrections is derived which involves only BFKL kernels. We discuss possible implications of this representation, including the possibility of finding…
Using reggeon diagrams as a partial implementation of $t$-channel unitarity, $O(g^4)$ corrections to the BFKL evolution equation have been obtained. We describe the spectrum and holomorphic factorization properties of the resulting…
A formula to unitarize the leading-log BFKL-Pomeron amplitude is derived using a coherent property of two-body collision in the peripheral region. This procedure also allows an algebraic characterization of the Reggeon in QCD based on…
The importance of polarised gluons fragmenting into $\Lambda$ in the polarised $e^+ e^-$ annihilation is discussed using the Altarelli-Parisi evolution equations satisfied by the quark and gluon fragmentation functions. In this context, the…
The exclusive process e+ e- -> e+ e- rho^0_L rho^0_L allows to study various dynamics and factorization properties of perturbative QCD. At moderate energy, we demonstrate how collinear QCD factorization emerges, involving generalized…
We derive the Leading Order DGLAP evolution of gluon distribution function in the target light cone gauge starting from its standard operator definition. The derivation is performed using the background field formalism also employed in the…
The Balitsky-Fadin-Kuraev-Lipatov (BFKL) evolution equation is known to be ``unstable'' with respect to fluctuations in gluon virtuality, transverse momentum and energy requiring to go beyond the leading order BFKL. Still, these…
Theoretical predictions show that at low values of Bjorken $x$ the spin structure function, $g_1$ is influenced by large logarithmic corrections, $ln^2(1/x)$, which may be predominant in this region. These corrections are also partially…
This paper introduces a transverse-momentum dependent (TMD) factorization scheme designed to unify both large and small Bjorken-x regimes. We compute the next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to the gluon TMD…
An approach is elaborated for calculation of "all loop" contributions to the non-singlet evolution kernels from the diagrams with renormalon chain insertions. Closed expressions are obtained for sums of contributions to kernels $P(z)$ for…
We consider the perturbative (weak field) limit of the small $x$ QCD evolution equation for quadrupole, the normalized trace of four Wilson lines in the fundamental representation, which appears in di-hadron angular correlation in high…
We present two novel results about the universal structure of radiative QED amplitudes in the soft and in the collinear limit. On the one hand, we extend the well-known Low-Burnett-Kroll theorem to the one-loop level and give the explicit…
The exclusive process e+ e- -> e+ e-rho0_L rho0_L allows to study various dynamics and factorization properties of perturbative QCD. At moderate energy, we demonstrate how collinear QCD factorization emerges, involving either generalized…
It is argued that the QCD dipole picture allows to build an unified theoretical description -based on BFKL dynamics- of the total and diffractive nucleon structure functions. This description is in qualitative agreement with the present…
We present the third-order contributions to the quark-gluon and gluon-quark timelike splitting functions for the evolution of fragmentation functions in perturbative QCD. These quantities have been derived by studying physical evolution…
We considerably extend our previous analysis of the implementation of an absorptive boundary condition, which mimics saturation effects, on the linear CCFM evolution. We present detailed results for the evolution of the unintegrated gluon…
Using repeated Laplace transform techniques, along with newly-developed accurate numerical inverse Laplace transform algorithms, we transform the coupled, integral-differential NLO singlet DGLAP equations first into coupled differential…
Equation for the sum of BFKL pomeron fan diagrams is rederived by direct summation and solved numerically for rapidities $y\leq 50$. At high rapidities y>20 the resulting cross-sections for the scattering of a longitudinally polarized…
We analyze the order-$\alpha_s^2$ QCD corrections to semi-inclusive deep inelastic scattering and present results for processes initiated by a gluon. We focus in the most singular pieces of these corrections in order to obtain the hitherto…