Related papers: A quantitative study of two-loop splitting in doub…
The soft physics approach to form factors and Compton scattering at moderately large momentum transfer is reviewed. It will be argued that in that approach the Compton cross section is given by the Klein-Nishina cross section multiplied by…
Higher-order QED effects play an important role in precision measurements of nucleon elastic form factors in electron scattering. Here we introduce a two-photon exchange QED correction to the parity-violating polarization asymmetry of…
We present the two-loop virtual QCD corrections to the scattering of massless distinct quarks in conventional dimensional regularisation. The structure of the infrared divergences agrees with that predicted by Catani while expressions for…
We study the $W^+W^-$ and $Z^0Z^0$ electroweak boson production in double parton scattering using QCD evolution equations for double parton distributions. In particular, we analyze the impact of splitting terms in the evolution equations on…
We present results on two-parton densities in coordinate space, which capture a fuller dynamical picture of the proton's internal structure, including information on the relative position between quarks and gluons in the transverse plane.…
We introduce a general expression which enables the parton distribution, unintegrated over the parton transverse momentum, to be obtained from the conventional parton densities. We use the formalism to study the effects of the transverse…
We perform a detailed investigation of multiple hard interactions in hadron-hadron collisions. We discuss the space-time, spin and color structure of multiple interactions, classify different contributions according to their power behavior…
Parton distribution functions are crucial to understand the internal kinematics of hadrons. There are currently a large number of distribution functions on the market, and thanks to today's technology, performing computational analysis of…
We review some recent results about the computation of mixed QCD-QED corrections beyond the leading order in perturbation theory. We start by considering the effects induced in the Altarelli-Parisi equations and the partonic distributions.…
The higher-order corrections become increasingly important with experiments reaching sub-percent level of uncertainty as they look for physics beyond the Standard Model. Our goal is to address the full set of two-loop electroweak…
The spin-dependent cross sections for semi-inclusive lepton-nucleon scattering are derived in the framework of collinear factorization, including the effects of masses of the target and produced hadron at finite momentum transfer squared…
This is a review of the program we started in 1968 to understand and generalize Bjorken scaling and Feynman's parton model in a canonical quantum field theory. It is shown that the parton model proposed for deep inelastic electron…
Parametrization of nuclear parton distributions is investigated in the leading order of alpha_s. The parton distributions are provided at Q^2=1 GeV^2 with a number of parameters, which are determined by a chi^2 analysis of the data on…
The asymptotic collinear factorisation theorem, which holds for diffractive deep-inelastic scattering, has important modifications in the sub-asymptotic HERA regime. We use perturbative QCD to quantify these modifications. The diffractive…
We discuss two collider processes which combine a diffractively produced $\rho$ meson separated by a large rapidity gap from a hard exclusive scattering of a Pomeron on a nucleon, giving rise to a lepton pair or to a second meson. These two…
Applications of perturbative QCD to hard exclusive electroproduction processes in the Bjorken limit at small invariant momentum transfer t bring in a new type of parton distributions which have hybrid properties, resembling both the parton…
We investigate the potential to observe double parton scattering at the Large Hadron Collider in p p -> W b bbar X -> l nu b bbar X at 7 TeV. Our analysis tests the efficacy of several kinematic variables in isolating the double parton…
Nucleon structure functions, as measured in lepton-nucleon scattering, have historically provided a critical observable in the study of partonic dynamics within the nucleon. However, at very large parton momenta it is both experimentally…
We present a model calculation of leading order interference fragmentation functions arising from the distribution of two hadrons produced in the same jet of a fragmenting quark in a hard process. Using a simple spectator model for the…
We explore the properties of two-point cosmic propagators when Perturbation Theory (PT) loop corrections are consistently taken into account. We show in particular how the interpolation scheme proposed in arXiv:1112.3895 can be explicitly…