Related papers: QCD Jets and Parton Showers
I discuss how to sample the space of parton momenta in order to best perform the numerical integrations that lead to a calculation of three jet cross sections and similar observables in electron-positron annihilation.
We present an analytic expression for the four-jet rate in e+e- annihilation, calculated using the coherent branching formalism in the Durham scheme. Our result resums all the leading and next-to-leading kinematic logarithms to all orders…
We present a new approach to combine multiple NLO parton-level calculations matched to parton showers into a single inclusive event sample. The method provides a description of hard multi-jet configurations at next-to leading order in the…
A new model of QCD parton shower is proposed which is dedicated to two-photon process in $e^+ e^-$ scattering. When hadron jets are produced, the photon may resolve into quark-antiquark pairs so that the structure functions of the photon…
A review of multijet rates and event-shape variables sensitive to multijet configuration with applications to measurements of alpha_s, QCD color factors and tests of power corrections is presented
We derive the probability for rapidity gaps in a parton cascade and investigate the dual connection with hadronic final states. A good description of observations in e+e- annihilations is obtained by perturbative QCD calculations in MLLA…
We have implemented a systematic procedure for combining parton shower algorithms with next-to-leading order QCD calculations for the case of jet production in deep-inelastic electron-proton scattering. Using this method we have computed…
We report on the next-to-leading order QCD calculation for e+ e- --> 4 jets. We explain some modern techniques which have been used to calculate the one-loop amplitudes efficiently. We further report on the general purpose numerical program…
After a discussion on the meaning of "jets" in the context of nucleus-nucleus collisions, the distortions of the profile of a parton shower induced by the presence of a medium is investigated in a QCD-inspired model that implements the…
The generator QEDPS, a parton shower model in QED, developed by the present authors has been improved. By a careful study on the shower algorithm it was found that some finite contributions have been missed in the original version. They are…
We present a new formalism for parton shower simulation of QCD jets, which incorporates the following features: invariance under boosts along jet axes, improved treatment of heavy quark fragmentation, angular-ordered evolution with soft…
The second-order QCD matrix elements give a very good agreement with experimental data on the angular distributions of the four-jet events in e+e- collisions at the Z0 resonance energy. Unfortunately the description of the sub-jet structure…
Away from the strictly soft and collinear limit of QCD radiation the choice of evolution scale in a parton shower algorithm is ambiguous and several options have been implemented in existing Monte Carlo event generators for proton-proton…
Inclusive jet production will dominate the high $Q^{2}$ final states at the LHC.~In this work we try to estimate the up-to-date expectations, for high $E_{T}$ jets and their expected origin from the various parton-parton scattering…
We study electron-positron annihilations into six jets at the parton level in perturbative Quantum Chromo-Dynamics (QCD), via the elementary processes $e^+e^-\ar q\bar q gggg$, $e^+e^-\ar q\bar q q'\bar q' gg$ and $e^+e^-\ar q\bar q q'\bar…
Inclusion of the QED higher order radiative corrections in the two-photon process, e+e- -> e+e- mu+mu-, is examined by means of the structure function and the parton shower. Results are compared with the exact $O(\alpha)$ calculations and…
We study hadron production in jets by applying quark recombination to jet shower partons. With the jet showers obtained from PYTHIA and augmented by additional non-perturbative effects, we compute hadron spectra in e+ + e-collisions at…
The branching processes in parton showers are studied in perturbative QCD for both quark and gluon jets. The emphasis is on the nature of fluctuations of both the parton multiplicities and the spatial patterns of the final states. Effective…
We investigate the behaviour of jets at high-multiplicity using analytic techniques. We consider in detail the rates, areas and the intermediate splitting scales as a function of the number of jets. In each case, we are able to characterise…
A thorough verification of the distinct differences in the properties of quark and gluon jets is considered as one of the most instructive tests of the basic ideas of QCD. In the real life experiments such a comparison appears to be quite a…