Related papers: Experimental Studies of Power Corrections
We consider subleading power corrections to event shape variables in $e^+e^-$ collisions at the first order in the QCD coupling $\alpha_s$. We start from the jettiness variable $\tau_2$ and the $y_{23}$ resolution variable for the $k_T$ jet…
We assess the model discriminating power of a combined phenomenological analysis of mu -> e gamma and mu -> e conversion on different target nuclei, including the current hadronic uncertainties. We find that the theoretical uncertainties…
We calculate nuclear enhanced power corrections to structure functions measured in deeply inelastic lepton-nucleus scattering in Quantum Chromodynamics (QCD). We find that the nuclear medium enhanced power corrections at order of…
The power corrections in the Operator Product Expansion (OPE) of QCD correlators can be viewed mathematically as an illustration of the transseries concept, which allows to recover a function from its asymptotic divergent expansion.…
The new result for the third-order QCD corrections to R_{e^+e^-}, unlike the old, incorrect result, is nicely compatible with the principle-of-minimal-sensitivity optimization method. Moreover, it leads to infrared fixed-point behaviour:…
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…
The QCD coupling alpha_s is determined from a combined analysis of experimental e+e- and e-p jet data confronted to theoretical predictions of the energy evolution of the parton-to-hadron fragmentation functions (FFs) moments…
We compute the order alpha_s^2 corrections to the one particle inclusive electroproduction cross section of hadrons with non vanishing transverse momentum. We perform the full calculation analytically, and obtain the expression of the…
We calculate $(\sqrt{-t}/Q)^k $ and $(m/Q)^k$ power corrections with $k\le 4$, where $m$ is the target mass and $t$ is the momentum transfer, to several key observables in Deeply Virtual Compton Scattering (DVCS). We find that the power…
We present results obtained from a study of the structure of hadronic events recorded by the L3 detector at various centre-of-mass energies. The distributions of event shape variables and the energy dependence of their mean values are…
This report was prepared in the context of the LPCC "Electroweak Precision Measurements at the LHC WG" and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the…
We hypothesize that the correct power counting for charmonia is in the parameter Lambda_QCD/m_c, but is not based purely on dimensional analysis (as is HQET). This power counting leads to predictions which differ from those resulting from…
We present a systematic analysis of the processes $e^+ ~e^- \rightarrow e^+ ~e^- X$ to study the polarised and unpolarised photon structure functions. The effect of target photon mass, which manifests itself as new singly polarised…
Hadronization corrections to the thrust and related event shape distributions in the two-jet kinematical region of e+e- annihilation are summarized by nonperturbative shape functions. The moments of shape functions are given by universal…
In this paper we calculate the power corrections to the pion transition form factor within the framework of perturbative QCD approach on the basis of $k_T$ factorization. The power suppressed contributions from higher twist pion wave…
A generator with $\alpha^2$ order radiative correction effects, including both the initial state radiative corrections and the photon vacuum polarization corrections, is built for the full simulation of $e^+e^- \to hadrons $ in cross…
We report on a recent calculation of the electroweak O(\alpha^3\alpha_s) corrections to 3-jet production and related event-shape observables at e+e- colliders. The calculation properly accounts for the experimental photon isolation criteria…
Inclusive hadron production cross sections in e+e-collisions shed light on the fundamental fragmentation and hadronization processes. We present measurements of the inclusive spectra of charged pions, kaons and protons in hadronic events at…
The experimental data collected by KEDR and BESIII collaborations at the energies below charm quark thresholds are compared with the QCD expressions for the $e^+e^-$ annihilation R-ratio truncated at different orders of perturbation theory.…
We present numerical results on the recently completed $O(\alpha^2)$ initial state corrections to the process $e^+e^- \rightarrow \gamma^*/Z^*$, which is a central process at past and future high energy and high luminsoity colliders for…