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Related papers: Final state photon production at LEP

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The description of the polarized quark hadronization process is one of the most challenging problems in the physics of strong interactions. The various single hadron and dihadron fragmentation functions, that quantify this process, are…

High Energy Physics - Phenomenology · Physics 2019-07-22 Aram Kotzinian , Hrayr H. Matevosyan , Anthony W. Thomas

New results on inclusive production of Sigma^- and Lambda(1520) and on proton production in quark and gluon jets are presented. These results are based on 2 million hadronic Z decays collected with the DELPHI detector at LEP. They are…

High Energy Physics - Experiment · Physics 2007-05-23 V. Uvarov

A detailed investigation of the theoretical ambiguities present in the QCD description of photon production in $e^+e^-$ annihilation is given. It is pointed out that in a well-defined perturbative analysis it is necessary to subtract the…

High Energy Physics - Phenomenology · Physics 2009-10-22 Zoltan Kunszt , Zoltán Trócsányi

Fragmentation functions are one of the key components of the factorisation theorem used to calculate heavy-flavour hadron production cross sections. The non-perturbative nature of fragmentation functions necessitates that they are…

High Energy Physics - Experiment · Physics 2023-10-24 Antonio Palasciano

We present calculations of heavy quark and quarkonium production at CERN LEP2 in the k_T-factorization QCD approach. Both direct and resolved photon contribution are taken into account. The conservative error analisys is performed. The…

High Energy Physics - Phenomenology · Physics 2011-01-25 A. V. Lipatov , N. P. Zotov

We report on the first extraction of interference fragmentation functions from the semi-inclusive production of two hadron pairs in back-to-back jets in e+e- annihilation. A nonzero asymmetry in the correlation of azimuthal orientations of…

High Energy Physics - Phenomenology · Physics 2013-05-30 A. Courtoy , A. Bacchetta , M. Radici , A. Bianconi

We calculate the fragmentation function for a light quark to decay into a lepton pair to leading order in the QCD coupling constant. In the formal definition of the fragmentation function, a QED phase must be included in the eikonal factor…

High Energy Physics - Phenomenology · Physics 2009-11-07 Eric Braaten , Jungil Lee

We study inclusive charged-hadron production in collisions of quasireal photons at NLO in perturbative QCD, using fragmentation functions recently extracted from PEP and LEP1 data. We superimpose the direct (DD), single-resolved (DR), and…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Binnewies , B. A. Kniehl , G. Kramer

We present a thorough phenomenological analysis of the experimental data from Belle Collaboration for the transverse $\Lambda$ and $\bar\Lambda$ polarisation, measured in $e^+e^-$ annihilation processes, for the case of inclusive (plus a…

High Energy Physics - Phenomenology · Physics 2020-09-09 Umberto D'Alesio , Francesco Murgia , Marco Zaccheddu

The cross section for the inclusive photoproduction of large-p_T D^*+- mesons is calculated at next-to-leading order, adopting different approaches to describe the fragmentation of charm quarks into D^*+- mesons. We treat the charm quark…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. A. Kniehl , G. Kramer , M. Spira

We study the production of a large-pT photon in association with a jet in proton-proton collisions. We examine the sensitivity of the jet rapidity distribution to the gluon distribution function in the proton. We then assess the sensitivity…

High Energy Physics - Phenomenology · Physics 2009-07-09 Z. Belghobsi , M. Fontannaz , J. -Ph. Guillet , G. Heinrich , E. Pilon , M. Werlen

Fragmentation functions are determined for the pion and kaon by global analyses of charged-hadron production data in electron-positron annihilation. Accurate measurements were reported by the Belle and BaBar collaborations for the…

High Energy Physics - Phenomenology · Physics 2016-09-28 M. Hirai , H. Kawamura , S. Kumano , K. Saito

We study the production of photons accompanied by jets in large-Q2 deep inelastic scattering. Numerical results for the cross section differential with respect to the fraction of momentum z_gamma carried by a photon inside a jet at large…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. Gehrmann-De Ridder , G. Kramer , H. Spiesberger

We analyse LEP and PETRA data on single inclusive charged hadron cross-sections to establish new sets of Next-to-Leading order Fragmentation Functions. Data on hadro-production of large-$p_{\bot}$ hadrons are also used to constrain the…

High Energy Physics - Phenomenology · Physics 2010-03-25 L. Bourhis , M. Fontannaz , J. Ph. Guillet , M. Werlen

Deep inelastic electron-photon scattering is studied in the Q**2 range from 1.2 to 30 GeV**2 using the LEP1 data taken with the ALEPH, L3 and OPAL detectors at centre-of-mass energies close to the mass of the Z boson. Distributions of the…

High Energy Physics - Experiment · Physics 2012-08-27 ALEPH Collaboration , L3 Collaboration , OPAL Collaboration , LEP Two Photon Working Group

Fragmentation functions (FFs) describe the formation of final state particles from a partonic initial state. Precise knowledge of these functions is a key ingredient in accessing quantities such as the nucleon spin structure in…

Nuclear Experiment · Physics 2019-08-13 Martin Leitgab

We suggested that longitudinal polarization of Lambda produced in e+e- annihilation at LEP energies can provide useful information on hadronization mechanism in general and on testing the validity of different pictures for the spin content…

High Energy Physics - Phenomenology · Physics 2007-05-23 Liang Zuo-tang

The production of photons accompanied by jets in large-Q2 deep inelastic ep scattering is calculated in next-to-leading order. We describe how to consistently include contributions from quark-to-photon fragmentation and give numerical…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Gehrmann-De Ridder , G. Kramer , H. Spiesberger

A study of b quark hadronisation is presented using inclusively reconstructed B hadrons in about four million hadronic Z decays recorded in 1992-2000 with the OPAL detector at LEP. The data are compared to different theoretical models, and…

High Energy Physics - Experiment · Physics 2012-08-27 The OPAL collaboration

The total hadronic cross-section for the interaction of real photons is extracted from a measurement of the cross-section of the process e+e->e+e- + hadrons using a luminosity function for the photon flux and form factors for extrapolating…

High Energy Physics - Experiment · Physics 2009-10-30 Frank Waeckerle