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Related papers: New results on alpha_s and optimized scales

200 papers

NLO corrections to jet cross sections in DIS at HERA are studied, with particular emphasis on the two jet final state. High jet transverse momenta are a good criterion for the applicability of fixed order perturbation theory. A ``natural''…

High Energy Physics - Phenomenology · Physics 2007-05-23 Erwin Mirkes , Dieter Zeppenfeld

We report on a major milestone in the construction of logarithmically accurate final-state parton showers, achieving next-to-next-to-leading-logarithmic (NNLL) accuracy for the wide class of observables known as event shapes. The key to…

We compute for the first time the production rate for four jets in electron-positron annihilation at next-to-next-to-leading order. Our calculation exhibits the highest final-state jet multiplicity considered at this perturbative accuracy…

High Energy Physics - Phenomenology · Physics 2026-02-23 Xuan Chen , Dmitry Chicherin , Elliot Fox , Nigel Glover , Matteo Marcoli , Vasily Sotnikov , Huiting Sun , Hantian Zhang , Simone Zoia

In large-scale modern data analysis, first-order optimization methods are usually favored to obtain sparse estimators in high dimensions. This paper performs theoretical analysis of a class of iterative thresholding based estimators defined…

Statistics Theory · Mathematics 2016-10-11 Yiyuan She

The strong coupling alpha_s(M_Z^2) has been measured using hadronic decays of Z^0 bosons collected by the SLD experiment at SLAC. The data were compared with QCD predictions both at fixed order, O(alpha_s^2), and including resummed analytic…

High Energy Physics - Experiment · Physics 2008-11-26 K. Abe

The top quark mass measurement with ATLAS in the lepton plus jets channel is summarized from the perspective of the early data. Using the invariant mass of the three jets arising from the hadronic side as the estimator of the top quark…

High Energy Physics - Experiment · Physics 2009-08-24 Antoine Marzin

Hadronic event shape distributions from e+e- annihilation measured by the OPAL experiment at centre-of-mass energies between 91 GeV and 209 GeV are used to determine the strong coupling {\alpha}S. The results are based on QCD predictions…

High Energy Physics - Experiment · Physics 2015-05-20 The OPAL Collaboration

We introduce and motivate the method of effective charges, and consider how to implement an all-orders resummation of large kinematical logarithms in this formalism. Fits for QCD \Lambda and power corrections are performed for the e+e-…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. J. Maxwell

We present a new non-parametric statistic, called the weighed $\ell_2$ divergence, based on empirical distributions for sequential change detection. We start by constructing the weighed $\ell_2$ divergence as a fundamental building block…

Statistics Theory · Mathematics 2021-02-25 Liyan Xie , Yao Xie

In a recent paper we have shown how to optimally compute the differential and cumulative cross sections for massive event-shapes at $\mathcal{O}(\alpha_s)$ in full QCD. In the present article we complete our study by obtaining resummed…

High Energy Physics - Phenomenology · Physics 2020-10-28 Alejandro Bris , Vicent Mateu , Moritz Preisser

This article introduces definitions for a number of new event shapes and jet-rates in hadron-hadron dijet production. They are designed so as to be measurable in practice at the Tevatron and the LHC, and to be global so that they can be…

High Energy Physics - Phenomenology · Physics 2008-11-26 Andrea Banfi , Gavin P. Salam , Giulia Zanderighi

In this work we perform the first ever calculation of jet event shapes at hadron colliders at next-to-next-to leading order (NNLO) in QCD. The inclusion of higher order corrections removes the shape difference observed between data and…

High Energy Physics - Phenomenology · Physics 2023-04-05 Manuel Alvarez , Josu Cantero , Michal Czakon , Javier Llorente , Alexander Mitov , Rene Poncelet

This paper provides an alternative to penalized estimators for estimation and vari- able selection in high dimensional linear regression models with measurement error or missing covariates. We propose estimation via bias corrected least…

Methodology · Statistics 2016-05-11 Abhishek Kaul , Hira L. Koul , Akshita Chawla , Soumendra N. Lahiri

Recent results on the energy spectra in QCD jets are reported. Within the Modified Leading Logarithmic Approximation (MLLA) and the Local Parton Hadron Duality (LPHD) model one finds a very good description of the $e^+e^-$ data from the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wolfgang Ochs

Deep-inelastic ep scattering data, taken with the H1 detector at HERA, are used to study the event shape variables thrust, jet broadening, jet mass, C parameter, and two kinds of differential two-jet rates over a large range of ``relevant…

High Energy Physics - Experiment · Physics 2009-10-31 K. Rabbertz

Results from heavy flavour electroweak physics at LEP1 are reviewed together with measurements of 2-fermion processes at LEP2. For the former measurements the emphasis is on analyses of heavy quark forward-backward asymmetries, A_FB^b,c,…

High Energy Physics - Experiment · Physics 2007-05-23 T. Schoerner-Sadenius

Selected topics on precision tests of the Standard Model of the Electroweak and the Strong Interaction at the LEP $e^+e^-$ collider are presented, including an update of the world summary of measurements of $\alpha_s$, representing the…

High Energy Physics - Experiment · Physics 2007-05-23 S. Bethke

We show that standard next-to-leading order (NLO) perturbative QCD analyses used to extract $\alpha_{s}$ from LEP data do not serve to disentangle the completely unknown renormalization scheme (RS) invariant next-NLO (NNLO) and higher-order…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. T. Barclay , C. J. Maxwell , M. T. Reader

Top quark physics measurements performed using data from the ATLAS detector at the LHC rely on efficient reconstruction and precise calibration of leptons, jets and missing transverse energy. A review of the techniques used to reconstruct…

High Energy Physics - Experiment · Physics 2016-11-18 Richard Hawkings

Recent measurements of top quark properties with ${\rm t{\bar t}}$ events collected by the ATLAS experiment in proton-proton collisions at the center of mass energy $\sqrt{s}=8$ and $13$ TeV, are presented. The measurements of the top quark…

High Energy Physics - Experiment · Physics 2017-11-27 Frédéric Derue