相关论文: QCD Tests at HERA
The discriminators of quark-gluon jets developed for $pp$ collisions at the LHC can be used to measure the gluon jet fraction in a jet sample. It allows to measure various characteristics of the quark and gluon jets. The methodology of such…
We argue that the process of the proton diffraction into three jets in proton-nucleus scattering at LHC will allow to investigate the light-cone wave function of protons, generalized gluon densities in nuclei at small x, as well as the…
Many important QCD tests with jets and prompt photons have been performed with the experiments H1 and ZEUS at the HERA ep collider. This contribution focuses on results from jet and prompt photon photoproduction. In particular, the concept…
At HERA, the large flux of almost real photons accompanying the electron beam leads to the copious photoproduction of jets. Regions of small momentum fractions $x$ of the incoming particles are explored, where the density of partons is…
Measurements performed by the CMS experiment of the cross section for inclusive b-quark production in proton-proton collisions at sqrt(s) = 7 TeV are presented. The measurements are based on different methods, such as inclusive jet…
New measurements of dijet photoproduction at HERA provide information on the gluon density in the photon and on its quark densities at high x_gamma and high factorisation scales.
The cross section for the photoproduction of events containing three jets with a three-jet invariant mass of M_3J > 50 GeV has been measured with the ZEUS detector at HERA. The three-jet angular distributions are inconsistent with a uniform…
The collimation of average multiplicity inside quark and gluon jets is investigated in perturbative QCD in the modified leading logarithmic approximation (MLLA). The role of higher order corrections accounting for energy conservation and…
Measurements of inclusive-jet and dijet cross-sections in high-Q2 deep-inelastic scattering are presented together with a short overview of extractions of the strong coupling parameter alpha_S from jets. The data samples used were collected…
We propose a new phenomenological approach to establish QCD factorization of jet cross sections in the heavy-ion environment. Starting from a factorization formalism in proton-proton collisions, we introduce medium modified jet functions to…
A measurement is presented of dijet and 3-jet cross sections in low-|t| diffractive deep-inelastic scattering interactions of the type ep -> eXY, where the system X is separated by a large rapidity gap from a low-mass baryonic system Y.…
Hard processes in collider experiments typically produce QCD jets, which have long served as precision tests of QCD in the vacuum. More recently, heavy-ion programs at RHIC and the LHC have offered a novel perspective on jets, establishing…
Recent jet and jet substructure measurements at the LHC, and of machine-learning-based tagging techniques are presented using proton-proton collision data collected by the ATLAS and CMS experiments at CERN's Large Hadron Collider. These…
This contribution reports preliminary jet results in ppbar collisions at sqrt(s)=1.96 TeV from the CDF and D0 experiments. The jet inclusive cross section, measured using both the Midpoint and the K_T jet clustering algorithm, is compared…
Measurements of the total cross section for real and virtual photons on protons at center-of-mass energies in the range from 20 GeV to 270 GeV with photon virtualities up to 5000 GeV^2 are presented. For real photons this cross section can…
The dependence of the photon structure on the photon virtuality, Q^2, is studied by measuring the reaction e^+p\to e^+ + {\rm jet} + {\rm jet} + {\rm X} at photon-proton centre-of-mass energies 134 < W < 223 GeV. Events have been selected…
In high energy proton-proton collisions, collimated sprays of particles, called jets, result from hard scattered quarks or gluons. Jets are copiously produced in these collisions; however, the dynamic process through which quarks and…
Besides structure function measurements and jet physics, there is a lively collection of more specific QCD analyses at HERA. In this contribution we present three-jet angular correlations and subjet distributions measured in ep collisions…
The Quark-Gluon Plasma (QGP) is created in high energy heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). This medium is transparent to electromagnetic probes but nearly opaque to colored…
Inclusive jet and dijet double-differential cross sections have been measured in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector at the LHC. The cross sections were measured using jets clustered with…