Related papers: Illuminating the charged leptons in the proton
In this article, we investigate the potential of low-mass lepton pair production in proton-ion collisions at the LHC to constrain nuclear modifications of parton densities. Similarly to prompt photon production, the transverse momentum…
Originally it was thought that the proton is not divisible into smaller particles. However, from collision experiments it follows that it consists of a 'soup' of countless 'colored' elementary particles such as quarks and gluons that are…
High-energy proton-proton collisions at the LHC offer a stringent test of Quantum Chromodynamics (QCD) in the small-$x$, gluon-dominated regime. This study focus on a minimal, gluon-driven framework to describe the charged-particle…
We have studied the production of single isolated prompt photons in high energy proton-proton collisions at the RHIC ($\sqrt{s}$= 200 GeV) and the LHC ($\sqrt{s}$= 7 TeV) energies within the frame work of perturbative QCD upto next-to…
We investigate the QED Compton process (both elastic and inelastic) in unpolarized and longitudinally polarized electron-proton scattering. The cross section can be expressed in terms of the equivalent photon distribution of the proton. We…
At the LHC we are colliding protons, but it is not the protons that are doing the interacting. It is their constituents the quarks, antiquarks and gluons-collectively known as partons. We need to know how what fractional momentum of the…
We review the current status of Parton Distribution Function (PDF) determinations for unpolarized and longitudinally polarized protons and for unpolarized nuclei, which are probed by high-energy hadronic scattering in perturbative Quantum…
Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon splitting…
Understanding the fundamental structure of matter requires an understanding of how quarks and gluons are assembled to form hadrons and of the structure of the protons which are the colliding particles at LHC. The arrangement of quarks and…
We study the impact of differential isolated-photon+jet cross sections measured in proton-proton collisions at a center-of-mass energy of sqrt{s} = 7 TeV on the parton distribution functions (PDF) of the proton. Next-to-leading order…
An explicit evaluation of the double parton distribution functions (dPDFs), within a relativistic Light-Front approach to constituent quark models, is presented. dPDFs encode information on the correlations between two partons inside a…
Vector meson production in ultra-peripheral pA and AA collisions at the CERN Large Hadron Collider (LHC) are very sensitive to Parton Distribution Functions (PDF) as well as to their leading-order, next-to-leading-order, and medium…
Non-perturbative gauge-invariance under the strong and the weak interactions dictates that the proton contains a non-vanishing valence contribution from the Higgs particle. By introducing an additional parton distribution function (PDF), we…
We present the MMHT2015qed PDF set, resulting from the inclusion of QED corrections to the existing set of MMHT Parton Distribution Functions (PDFs), and which contain the photon PDF of the proton. Adopting an input distribution from the…
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 detailed comprehension of momentum fraction and energy dependence of proton structure functions is among the major difficulties in high-energy physics. Perturbative quantum chromodynamics (QCD) plays as an extensive foundation for…
The LHC has already provided many relevant measurements for the determination of parton distribution functions (PDFs). Measurements of the W and Z lepton distributions are of interest for flavor separation and in particular for the…
Double parton scattering (DPS) has become very relevant as a background to interesting analyses performed by the experiments at the LHC. It encodes knowledge of correlations between the proton constituents not accessible in single parton…
Exclusive photoproduction of dileptons, gamma p ->l+ l- p, will be measured in ultraperipheral collisions at LHC. The mechanism where the lepton pair comes from a heavy timelike photon radiated from a quark interferes with the pure QED…
We study a few basic photon- and lepton-initiated processes at the LHC which can be computed using the recently developed photon and lepton parton densities. First, we consider the production of a massive scalar particle initiated by…