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Related papers: Multijet Final States in e+e- Annihilation

200 papers

In this work we provide all the missing ingredients for calculating parity-violating 3-jet observables in e^+e^- collisions at next-to-leading order (NLO) including the full quark mass dependence. In particular we give explicit results for…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Bernreuther , A. Brandenburg , P. Uwer

Motivated by various excesses observed by the Fermi-LAT and AMS collaborations, we perform a detailed analysis of QCD uncertainties on particle spectra from dark-matter annihilation (or decay) into jets. When annihilated to SM particles,…

High Energy Physics - Phenomenology · Physics 2022-03-02 Adil Jueid

A quantitative description of the qualitative feature of multi-hadron final states known as the "number of jets" is given by a sequence of infrared finite shape observables (jet discriminators) that: take continuous values between 0 and 1;…

High Energy Physics - Phenomenology · Physics 2009-10-31 Fyodor V. Tkachov

Six--jet events via WW pairs, $e^+e^- \ar W^+W^- \ar q_1 \overline{q_1} q_2 \overline{q_2} g g$ are studied at tree level using helicity amplitudes. This is the dominant production mechanism for six--jet final states at Lep II energy. ISR…

High Energy Physics - Phenomenology · Physics 2009-10-28 E. Accomando , A. Ballestrero , E. Maina

We present the QCD analysis of D-parameter distribution in near-to-planar 3-jet e+e- annihilation events. We derive the all-order resummed perturbative prediction and the leading power suppressed non-perturbative corrections both to the…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Banfi , Yu. L. Dokshitzer , G. Marchesini , G. Zanderighi

We calculate the average multiplicity of jets in e+e- annihilation as a function of both the jet resolution parameter, y_cut, and the thrust T. Our result resums to all orders the leading and next-to-leading logarithms in y_cut and 1-T, and…

High Energy Physics - Phenomenology · Physics 2009-04-13 D. J. Miller , Michael H. Seymour

Recent results from CMS are reviewed for searches for supersymmetry in final states with multiple bottom quark jets. Results are based on the full 2012 CMS dataset consisting of 19.5 fb-1 collected at a center-of-mass energy of sqrt(s) = 8…

High Energy Physics - Experiment · Physics 2019-08-13 Keith A. Ulmer

We present a new implementation of the NNLO QCD corrections to three-jet final states and related event-shape observables in electron--positron annihilation. Our implementation is based on the antenna subtraction method, and is performed in…

High Energy Physics - Phenomenology · Physics 2017-12-06 Thomas Gehrmann , Nigel Glover , Alexander Huss , Jan Niehues , Hantian Zhang

We compute the next-to-next-to-leading order (NNLO) QCD corrections to the first five moments of six event shape variables related to three-particle final states in electron-positron annihilation; the thrust, the heavy jet mass, the…

High Energy Physics - Phenomenology · Physics 2009-06-11 A. Gehrmann-De Ridder , T. Gehrmann , E. W. N. Glover , G. Heinrich

Data from e+e- annihilation into hadrons at centre-of-mass energies between 91 GeV and 209 GeV collected with the OPAL detector at LEP, are used to study the four-jet rate as a function of the Durham algorithm resolution parameter ycut. The…

High Energy Physics - Experiment · Physics 2009-01-07 The OPAL Collaboration , G. Abbiendi

Analytic formulae are derived for the complete photon energy spectrum due to QED corrections to fermion pair production in case of a limited angular acceptance for the final state fermions. After a numerical integration over the energy of…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Bardin , M. Bilenky , A. Sazonov , Yu. Sedykh , T. Riemann , M. Sachwitz

Data from e+e- annihilation into hadrons collected by the JADE experiment at centre-of-mass energies between 14 and 44 GeV were used to study the 4-jet rate using the Durham algorithm as well as the first five moments of event shape…

High Energy Physics - Experiment · Physics 2017-08-23 Stefan Kluth

In the Standard Model the process e+e- -> gamma-gamma is fully described by QED. Measurements of the differential cross-sections from the four LEP experiments are compared to the QED expectation and limits are set on parameters describing…

High Energy Physics - Experiment · Physics 2017-08-23 K. Sachs

Elementary particle physics using beams from accelerators and cosmic rays are compared. In particular, recent results on the energy evolution of charged particle multiplicities, the differences between quark and gluon jets, and scaling…

High Energy Physics - Phenomenology · Physics 2007-05-23 Claus Grupen

Data from e+e- annihilation into hadrons collected by the JADE experiment at centre-of-mass energies between 14 GeV and 44 GeV are used to study the four-jet event production rate as a function of the Durham jet algorithm's resolution…

High Energy Physics - Experiment · Physics 2012-05-21 J. Schieck , S. Bethke , O. Biebel , S. Kluth , P. A. Movilla Fernandez , C. Pahl , the JADE Collaboration

We study electron-positron annihilations into six jets at the parton level in perturbative Quantum Chromo-Dynamics. We use helicity amplitude methods. Results are presented for the case of the Durham and Cambridge jet clustering algorithms…

High Energy Physics - Phenomenology · Physics 2009-10-30 Stefano Moretti

We give perturbative predictions for the distribution of the $C$-Parameter event shape variable in $e^+e^-$ annihilation, including resummation of large logarithms in the two-jet (small-$C$) region, matched to next-to-leading order results.…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Catani , B. R. Webber

We investigate the cross-section for the production of a low-mass colour-singlet cluster in $e^+e^-$ annihilation with a large rapidity gap between the colour-singlet cluster and the other jets. It is argued that such events are the…

High Energy Physics - Phenomenology · Physics 2009-09-11 J. Ellis , D. A. Ross

Total hadron multiplicities and multiplicities of hadrons in events with heavy quarks in $e^+e^-$ annihilation at the energies of LEP-1.5 and LEP-2 are calculated on the basis of QCD.

High Energy Physics - Phenomenology · Physics 2011-01-25 A. V. Kisselev , V. A. Petrov

Data from \epem annihilation into hadrons, collected by the \Jade experiment at centre-of-mass energies between 14 GeV and 44 GeV, are used to study moments of event shape distributions. Models with hadronisation parameters tuned to the LEP…

High Energy Physics - Experiment · Physics 2019-08-13 Christoph Pahl , Siegfried Bethke , Stefan Kluth , Jochen Schieck