Related papers: Factorization and transverse phase-space parton di…
This talk discusses the effective field theory view of deep inelastic scattering. In such an approach, the standard factorization formula of a hard coefficient multiplied by a parton distribution function arises from matching of QCD onto an…
Using Soft-Collinear Effective Theory we derive factorization formulae for semi-inclusive processes where a light hadron h fragments from a jet whose invariant mass is measured. Our analysis yields a novel "fragmenting jet function"…
We suggest that the ultrarelativistic collisions of heavy ions provide the simplest situation for the study of strong interactions which can be understood from first principles and without any model assumptions about the microscopic…
The singular behaviour of QCD squared amplitudes in the collinear limit is factorized and controlled by splitting kernels with a process-independent structure. We use these kernels to define collinear functions that can be used in QCD…
Dimensional analysis reveals general kinematic scaling rules for the momentum, mass, and energy dependence of Drell-Yan and quarkonium cross sections. Their application to mid-rapidity LHC data provides strong experimental evidence…
We study the transverse single-spin asymmetry for single-hadron production in proton-proton collisions within the framework of collinear twist-3 factorization in Quantum Chromodynamics. By taking into account the contribution due to parton…
The extension of the factorization theorems of perturbative QCD to power corrections associated with re-scattering in nuclear collisions is reviewed. The importance of hadron-nucleus collisions is discussed.
Recent BELLE measurements provide the cross section for single hadron production in $e^+e^-$ annihilations, differential in thrust and in the hadron transverse momentum with respect to the thrust axis. Universality breaking effects due to…
The production of hard photons in hadronic collisions is studied using Soft-Collinear Effective Theory (SCET). This is the first application of SCET to a physical, observable cross section involving energetic partons in more than two…
Global perturbative QCD analyses, based on large data sets from electron-proton and hadron collider experiments, provide tight constraints on the parton distribution function (PDF) in the proton. The extension of these analyses to nuclear…
The hadronization of a high-energy parton is described by fragmentation functions which are introduced through QCD factorizations. While the hadronization mechanism per se remains uknown, fragmentation functions can still be investigated…
We discuss heavy quark diffusion and radiation in an intermediate-momentum regime where finite mass effects can be significant. Diffusion processes are described in the Fokker-Planck approximation for soft momentum transfer, while radiative…
We illustrate how electron Parton Distribution Functions (PDFs) with next-to-leading collinear logarithmic accuracy must be employed in the context of perturbative predictions for high-energy $e^+e^-$-collision processes. In particular, we…
In ultrarelativistic heavy-ion experiments, one estimates the centrality of a collision by using a single observable, say $n$, typically given by the transverse energy or the number of tracks observed in a dedicated detector. The…
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…
Using the framework that interpolates between the leading power limit of the Color Glass Condensate and the High Energy (or $k_{T}$) factorization we calculate the direct component of the forward dijet production in ultra-peripheral…
Nonrelativistic Quantum Chromodynamics (NRQCD) breaks down in the region of low transverse momentum, where the transverse momentum of the produced quarkonium state is sensitive to multiple scattering with the incoming hadron and to soft…
We present a factorization theorem valid near the kinematic threshold $z=Q^2/\hat{s}\to 1$ of the partonic Drell-Yan process $q\bar q\to\gamma^*+X$ for general subleading powers in the $(1-z)$ expansion. We then consider the specific case…
We calculate the nuclear inclusive and diffractive cross sections for heavy quark photoproduction within a phenomenological saturation approach. The nuclear cross section is obtained by the extension of the saturation model through…
This Ph.D.~thesis is divided into two distinct parts. The first part focuses on hard exclusive scattering processes in Quantum Chromodynamics (QCD) at high energies, while the second part delves into spin phenomena at the Large Hadron…