Related papers: MLLA Parton Spectra Compared to ARIADNE
The interpretation of experimental measurements at the LHC requires accurate theoretical predictions for exclusive observables, and in particular the summation of soft and collinear radiation to all orders in perturbation theory. We report…
Quark spin effects in $e^+e^-$ annihilation to pseudoscalar and vector mesons are implemented for the first time in the PYTHIA Monte Carlo event generator. The spin-dependent fragmentation of the string stretched between the produced…
We describe a Monte Carlo event generator for the simulation of QCD-instanton induced processes in deep-inelastic scattering (HERA). The QCDINS package is designed as an ``add-on'' hard process generator interfaced to the general hadronic…
We present an introductory discussion of deep-inelastic lepton-proton scattering as a means to probe the substructure of the proton. A resume of QCD is given, emphasizing the running of the coupling constant and the DGLAP evolution…
We pursue the hypothesis that the events with a large rapidity gap, observed at HERA, reflect the scattering of electrons off lumps of wee partons inside the proton. A simple scaling behaviour is predicted for the diffractive structure…
The moments of the single inclusive momentum distribution of hadrons in QCD jets, are studied in the next-to-modified-leading-log approximation (NMLLA) including next-to-leading-order (NLO) corrections to the alpha_s strong coupling. The…
Recent results from the HERA ep collider are reviewed in these proceedings. The results are from measurements that probe QCD at high-energy scales, as defined by $Q^2$, the four-momentum-transfer squared of the collisions. These…
We discuss $Z$ -production in the deep inelastic process $e + P \to e + Z + X$ in the context of the Standard Model using the Parton Model. In contrast to the deep inelastic $eP$-scattering ($e + P \to e + X$), where the choice of…
After a brief introduction into the phenomenology of instantons, results from instanton perturbation theory applied to deep-inelastic electron proton scattering are summarized. Based on event signatures derived from Monte Carlo studies,…
Measurements of alpha_s from e+e- annihilation experiments are reviewed and compared with measurements from other processes. Highlights are presented of recent QCD studies in e+e- annihilation at the Z0 resonance.
An algorithm is presented in which the Colour-Dipole Cascade Model as implemented in the Ariadne program is corrected to match the fixed order tree-level matrix elements for e+e- -> n jets. The result is a full parton level generator for…
We derive the angular correlation functions between an arbitary number of partons inside a quark or gluon jet emerging from a high energy hard collision. As an application results for the correlation in the relative angle between two…
The QCD coupling $\alpha_s$ is extracted from the energy evolution of the first two moments (multiplicity and mean) of the parton-to-hadron fragmentation functions at low fractional hadron momentum $z$. Comparisons of the experimental…
We study the prospects for HERA with polarized electron and/or proton beams to determine the functions describing the fragmentation of a longitudinally polarized parton into a polarized Lambda baryon. We examine both semi-inclusive…
The Standard Model prediction for muon-electron scattering beyond leading order requires the inclusion of QCD contributions which cannot be computed perturbatively. At next-to- and next-to-next-to-leading order, they arise from one- and…
We present new sets of fragmentation functions for protons and inclusive charged hadrons obtained in combined NLO QCD analyses of single-inclusive hadron production in electron-positron annihilation, proton-proton collisions, and…
The analyses of recent LEP data provide us with a rich ground for pQCD and LPHD tests. A number of non-trivial effects predicted in the framework of MLLA are experimentally verified. Recent measurements also enrich our knowledge about the…
The infrared exponentiation properties of dimensionally-regularized multi-loop scattering amplitudes are typically hidden at the level of the integrand, materializing only after integral evaluation. We address this long-standing problem by…
Using the QCD string approach the adiabatic potentials and spectra of b\bar b-hybrid mesons are calculated. The results are compared to lattice studies.
We discuss the GENEVA Monte Carlo framework, which combines higher-order resummation (NNLL) of large Sudakov logarithms with multiple next-to-leading-order (NLO) matrix-element corrections and parton showering (using PYTHIA8) to give a…