Related papers: Some problems of the pQCD jet calculus
The perturbative quantum chromodynamics (pQCD) has been extremely successful in the prediction and description of main properties of quark and gluon jets. There are, however, some problems of the jet calculus with the higher order…
The second and third factorial moments of the multiplicity distributions of gluon and quark jets are calculated up to the next-to-next-to-next-to leading order in perturbative QCD, using the equations for generating functions. The results…
The energy evolution of average multiplicities of quark and gluon jets is studied in perturbative QCD. Higher order (3NLO) terms in the perturbative expansion of equations for the generating functions are found. First and second derivatives…
The solution of the equations for the generating functions of multiplicity distributions of quark and gluon jets in higher order 3NLO perturbative QCD is obtained. The non-perturbative effects are discussed as well. The results are compared…
Theoretical predictions used in experimental analysis of LHC data have an inherent theoretical uncertainty associated to the relevant order in the perturbative expansion that the observable is computed. In this talk we briefly introduce and…
We discuss the problems that arise when one wishes to extend the existing general methods of computing radiative corrections to QCD jet cross sections to beyond next-to-leading order. Then we present a subtraction scheme that can be defined…
Analytic predictions for the energy dependence of the mean multiplicities in gluon and quark jets are presented at the next-to-next-to-next-to-leading order (3NLO) of perturbative QCD and are compared to experiment. The 3NLO correction to…
For precision studies with QCD observables at colliders, higher order perturbative corrections are often mandatory. For exclusive observables, like jet cross sections or differential distributions, these corrections were until recently only…
The QCD evolution equations in Modified Leading Log Approximation for the factorial moments of the multiplicity distribution in quark and gluon jets are numerically solved with initial conditions at threshold by fully taking into account…
The difference between the ratio of multiplicities and the ratio of their derivatives on energy for gluon and quark jets is calculated up to next-to-next-to leading order of perturbative QCD. Its non-zero value is uniquely defined by the…
Quantum chromodymamics (QCD) approach to the problem of multiplicity distributions in high energy particle collisions is described. The solutions of QCD equations for generating functions of the multiplicity distributions in gluon and quark…
Multi-jet rates at hadron colliders provide a unique possibility for probing Quantum Chromodynamics (QCD), the theory of strong interactions. By comparing theory predictions with collider data, one can directly test perturbative QCD,…
We present a new approach to consider and include both the perturbative and the non-perturbative contributions to the multiplicities of gluon and quark jets. Thanks to this new method, we have included for the first time new contributions…
A brief overview of some recently active topics in perturbative QCD, including: string-inspired recursion techniques at tree level; recursion approaches and automation of standard techniques for 1-loop calculations; the status of NNLO jet…
We review recent developments in the QCD description of jet production and modification in reactions with heavy nuclei at relativistic energies. Our goal is to formulate a perturbative expansion in the presence of nuclear matter that allows…
We briefly describe a new general algorithm for carrying out QCD calculations to next-to-leading order in perturbation theory. The algorithm can be used for computing arbitrary jet cross sections in arbitrary processes and can be…
We develop a new formalism for computing and including both the perturbative and nonperturbative QCD contributions to the scale evolution of average gluon and quark jet multiplicities. The new method is motivated by recent progress in…
Differences between the properties of gluon and quark jets have been convincingly established by experiments at LEP. Quantitative tests of QCD analytic predictions for these differences have not been possible, however, because of…
We give an introduction to perturbative Quantum Chromodynamics, focusing on a pedagogical description of concepts and methods to calculate cross sections measured at high energy colliders. After introducing basic concepts that allow for a…
These proceedings discuss some of the highlights of recent research in perturbative QCD as it relates to the LHC. Topics covered include the new generation of Monte Carlo event generators, the revolution that is occurring in NLO…