相关论文: Hadronic event structure, power corrections and th…
The Standard Model Lagrangian requires the values of the fermion masses, the Higgs mass and three other experimentally well-measured quantities as input in order to become predictive. These are typically taken to be $\alpha$, $G_\mu$ and…
The nucleon structure functions probed in deep-inelastic scattering at large virtualities form an important tool to test Quantum Chromdynamics (QCD) through precision measurements of the strong coupling constant $\alpha_s(M_Z^2)$ and the…
The QCD running coupling $\alpha_s(Q^2)$ sets the strength of the interactions of quarks and gluons as a function of the momentum transfer $Q$. The $Q^2$ dependence of the coupling is required to describe hadronic interactions at both large…
Exploration of the small $x$ kinematic region by the HERA experiments led to a revival of some models which existed before the advent of Quantum Chromo Dynamics (QCD) as the theory of the strong interactions. Predictions of these models for…
A Procedure is outlined that may be used as a starting point for a perturbative treatment of theories with permanent confinement. By using a counter term in the Lagrangian that renormalizes the infrared divergence in the Coulomb potential,…
Deep inelastic e^+ scattering data, taken with the H1 detector at HERA, are used to study the event shape variables thrust, jet broadening and jet mass in the current hemisphere of the Breit frame over a large range of momentum transfers Q…
We present a detailed analysis of the use of heavy quark fragmentation into heavy hadrons for testing the heavy quark effective theory through comparison of the measured fragmentation parameters of the $c$ and $b$ quarks. Our analysis is…
Gauge theories are characterised by long range interactions. Neglecting these interactions at large times, and identifying the Lagrangian matter fields with the asymptotic physical fields, leads to the infra-red problem. In this paper we…
The `renormalon' or `dispersive' method for estimating non-perturbative corrections to QCD observables is reviewed. The corrections are power-suppressed, i.e. of the form $A/Q^p$ where $Q$ is the hard process momentum scale. The renormalon…
In this proceedings we discuss a prescription to extract the QCD strong coupling constant at $N^{3}LO$ precision in perturbative QCD using a combination of ${\cal{O}}(\alpha_{S}^{3})$ calculations in pQCD and estimations of the…
The potential of the TESLA linear e+e- collider to determine the strong coupling constant, alpha_S, at 500 GeV is investigated. Experimental complications due to background from W- and Z-pairs, top-production, initial state photon radiation…
In this talk we introduce the main features of a QCD-based model in which the coupling $\alpha_{s}$ is constrained by an infrared mass scale. We show recent applications of this model to hadron-hadron collisions, gap survival probability…
Underlying events dominate most of the hadronic activity in p$-$p collisions and are spanned from perturbative to non-perturbative QCD, having a sensitivity ranging from the multi-scale to very low-x scale physics. A detailed understanding…
Hadronic resonances are unique probes that allow the properties of heavy-ion collisions to be studied. Topics that can be studied include modification of spectral shapes, in-medium energy loss of parsons, vector-meson spin alignment,…
Hadronic jets are extremely abundant at the LHC, and testing QCD in various corners of phase-space is important to understand backgrounds and some specific signatures of new physics. In this article, various measurements aiming at probing…
We present precision results for distributions in global event shapes that can be measured at hadron colliders within experimental limitations. These predictions are obtained by combining exact next-to-leading order (NLO) with the all-order…
Various QCD studies based on jet observables in hadronic final states in deep-inelastic scattering and hadron-hadron collisions are presented. Measured quantities are event shape variables, jet rates and jet cross sections. QCD analyses…
Data from electron positron annihilations at different center of mass energies are collected by the four LEP experiments. Direct tests of hard QCD are performed by measuring and analysing event shape observables.
I review the status of the comparisons between a few measurements at hadronic colliders and perturbative QCD predictions, which emphasize the need for improving the current computations. Such improvements will be mandatory for a…
The `XIIIth Quark Confinement and the Hadron Spectrum' conference (Confinement 2018) contained a `Round Table Discussion' on the status of the determinations of the strong coupling $\alpha_s(m_Z)$ as well as prospects for future…