Related papers: Expanding running coupling effects in the hard Pom…
We present a lattice determination of the $\Lambda$ parameter in three-flavor QCD and the strong coupling at the Z pole mass. Computing the nonperturbative running of the coupling in the range from $0.2\,$GeV to $70\,$GeV, and using…
A robust thermodynamic argument shows that a small reduction of the effective coupling constant $\alpha$ of QED greatly enhances the Compton scattering cross section and that the Thomson scattering length is connected to a fundamental scale…
We discuss the significance of the next-to-leading order term in the BFKL equation on the energy dependence of diffractive processes controlled by the perturbative QCD pomeron. It is shown that whereas the large negative corrections do…
The QCD-coupling is a necessary input in the computation of many observables, and the parametric error on input parameters can be a dominant source of uncertainty. The coupling can be extracted by comparing high order perturbative…
In this paper we consider the influence of non-perturbative corrections on the large $ b $ (impact parameter) behavior of the BFKL amplitude. This is done in the framework of a model where such ``soft'' corrections are taken into account in…
We consider the (process-independent) Green function for the BFKL equation in the next-to-leading order approximation, with running coupling, and explain how, within the semi-classical approximation, it is related to Green function of the…
Following recent progresses in the understanding of high-energy scattering in QCD, we derive the first phenomenological consequences of Pomeron loops, in the context of both inclusive and diffractive deep inelastic scattering. In…
Based on the dual representation in terms of the recently established eigenfunctions of the evolution kernel in heavy-quark effective theory, we investigate the description of the B-meson light-cone distribution amplitude (LCDA) beyond…
We find the BFKL Pomeron intercept at N=4 supersymmetric gauge theory in the form of the inverse coupling expansion j0=2-2/lambda**(1/2)-1/lambda + 1/4 1/lambda**(3/2) + 2(1+3zeta3)/lambda**(2) + O(1/lambda**(5/2)) with the use of the…
We report on recent progress on perturbative QCD calculations of certain exclusive rare weak $B$ meson decays involving hard photons. In the limit of a photon energy $E_\gamma$ much larger than $\Lambda_{QCD}$, the amplitudes for such…
Within the framework of a (1+1)--dimensional model which mimics high energy QCD, we study the behavior of the cross sections for inclusive and diffractive deep inelastic $\gamma^*h$ scattering cross sections. We analyze the cases of both…
We compute the full vacuum polarization tensor in the minimal QED extension. We find that its low-energy limit is dominated by the radiatively induced Chern-Simons-like term and the high-energy limit is dominated by the c-type coefficients.…
We investigate the basic features of the gluon density predicted by a renormalisation group improved small-x equation which incorporates both the gluon splitting function at leading collinear level and the exact BFKL kernel at…
After a brief introduction to low-x QCD and to resummation approaches, I illustrate the predictions for the gluon Green function and splitting function of a recent renormalization-group improved small-x resummation scheme. I argue, on this…
We argue that deep-inelastic diffractive scaling provides fundamental insight into the QCD Pomeron. The logarithmic scaling violations seen experimentally are in conflict with the scale-invariance of the BFKL Pomeron and with…
We make a critical analysis on the free parameters of the Cornell potential $-4\alpha_{s}/3r+br+c$ and provide a parameterisation space for the strong coupling constant $\alpha_{s}$ and the constant shift $c$ for choosing linear part as…
We examine the parametrization of the QCD coupling in the Bethe-Salpeter equations for the hard and Regge processes and determine the argument of alpha_s of the factorized gluon. Our analysis shows that for the hard processes alpha_s =…
The intercept of the supercritical Pomeron is examined with the use of different forms of the scattering amplitudes of the bare Pomeron. The one-to-one correspondence between the eikonal phase and the ratio of the elastic and total cross…
A continuous sequence of infinitesimal unitary transformations is used to diagonalize the quantum sine-Gordon model for \beta^2\in(2\pi,\infty). This approach can be understood as an extension of perturbative scaling theory since it links…
We report on recent experimental and theoretical developments in our understanding of the QCD running coupling \alpha_s in QCD's nonperturbative regime. They allow us to analytically compute the hadron mass spectrum, with \Lambda_s the only…