Related papers: Structure functions from renormalization group imp…
We present calculations of the structure functions F_2(x,Q^2) and F_L(x,Q^2), concentrating on small x. After discussing the standard expansion of the structure functions in powers of \alpha_s(Q^2) we consider a leading-order expansion in…
We review the possibility to use the renormalons emerging in the perturbation series of the twist-2 part of the nonsinglet structure functions FL, F2, F3, and g1 to make approximate predictions for the magnitude of the appertaining twist-4…
Fits to the final combined HERA deep-inelastic scattering cross-section data within the conventional DGLAP framework of QCD have shown some tension at low $x$ and low $Q^2$. A resolution of this tension incorporating $\ln(1/x)$-resummation…
We compute the longitudinal proton structure function F_L from the k_T factorization scheme, using the unified DGLAP/BFKL resummation approach at small x for the unintegrated gluon density. The differences between the k_T factorization,…
I present a simplified model for the gluon Green's function governing high-energy QCD dynamics, in arbitrary space-time dimensions. The BFKL integral equation (either with or without running coupling) reduces to a second order differential…
I present a theoretical discussion of the uncertainties related to the QCD analysis of the proton structure function $F_2(x,Q^2)$ at small $x$. The role played by the `unphysical' gluon density is pointed out. It is shown how the study of…
A new measurement of the proton structure function $F_2(x,Q^2)$ is reported for momentum transfers squared $Q^2$ between 1.5 GeV$^2$ and 5000 GeV$^2$ and for Bjorken $x$ between $3\cdot 10^{-5}$ and 0.32 using data collected by the HERA…
The nonlinear Balitsky-Kovchegov equation at small x is solved numerically, incorporating impact parameter dependence. Confinement is modeled by including effective gluon mass in the dipole evolution kernel, which regulates the splitting of…
We study soft-gluon radiation for heavy quark production in charged-current Deep Inelastic Scattering processes. We resum large-x contributions to the MSbar coefficient function to next-to-leading logarithmic accuracy and present results…
Functional renormalization group (FRG) has become a diverse and powerful tool to derive effective low-energy scattering vertices of interacting many-body systems. Starting from a non-interacting expansion point of the action, the flow of…
The renormalization group flow is presented for the two-dimensional sine-Gordon model within the framework of the functional renormalization group method by including the wave-function renormalization constant. The…
From the new measurement of F_L at HERA we derive fixed-Q^2 averages <F_L/F_2>. We compare these with bounds which are rigorous in the framework of the standard dipole picture. The bounds are sharpened by including information on the charm…
Reentrant computation-recursive self-coupling in which a network continuously reinjects and reinterprets its own internal state-plays a central role in biological cognition but remains poorly characterized in neural network architectures.…
Gluon distribution function at small x is computed using the extended McLerran-Venugopalan model. A lipatov like enhancement is seen as well as a non-trivial transverse momentum dependence which is estimated. It is shown that gluon density…
It is well known that there are persistent statistical tensions with the standard model in the low Q2 HERA deep inelastic scattering neutral current data characterized by a turn-over of F2(x, Q2) at low x and low Q2. One important…
We discuss the distinct approaches for high density QCD (hdQCD) in the asymptotic regime of large values of parton density. We derive the AGL equation for running coupling constant and obtain the asymptotic solution, demonstrating that the…
Results are presented of a study of the experimental and theoretical accuracy one may achieve at HERA in measuring the strong coupling constant alpha_s and the gluon distribution from scaling violations of F2 structure functions.
We report on the extension of the data fitting considering the QCD inspired model based on the summation of gluon ladders applied to the $ep$ scattering. In lines of a two Pomeron approach, the structure function $F_2$ has a hard piece…
At very high energies, the relevant component of the hadron wavefunction can be described as a Color Glass Condensate, i.e., a state of high density gluonic matter whose distribution is random, but frozen over the relevant time scales. The…
The latest measurements of $F_2$ at HERA allow for a {\it combination} of gluon and sea quark distributions at small $x$ that is significantly different from those of existing parton sets. We perform a new global fit to deep-inelastic and…