Results 31 to 40 of about 1,867 (174)
Rational terms of UV origin at two loops
Journal of High Energy Physics, 2020 The advent of efficient numerical algorithms for the construction of one-loop amplitudes has played a crucial role in the automation of NLO calculations, and the development of similar algorithms at two loops is a natural strategy for NNLO automation ...
Stefano Pozzorini +2 more
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NNLO virtual and real leptonic corrections to muon-electron scattering
Journal of High Energy Physics, 2021 The recently proposed MUonE experiment at CERN aims at providing a novel determination of the leading order hadronic contribution to the muon anomalous magnetic moment through the study of elastic muon-electron scattering at relatively small momentum ...
Ettore Budassi +7 more
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The two-loop perturbative correction to the (g − 2) μ HLbL at short distances
Journal of High Energy Physics, 2021 The short-distance behaviour of the hadronic light-by-light (HLbL) contribution to (g − 2) μ has recently been studied by means of an operator product expansion in a background electromagnetic field.
Johan Bijnens +3 more
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Isospin-breaking effects in the three-pion contribution to hadronic vacuum polarization
Journal of High Energy Physics, 2023 Isospin-breaking (IB) effects are required for an evaluation of hadronic vacuum polarization at subpercent precision. While the dominant contributions arise from the e + e − → π + π − channel, also IB in the subleading channels can become relevant for a ...
Martin Hoferichter +3 more
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PRECISION STUDY OF POSITRONIUM: TESTING BOUND STATE QED THEORY [PDF]
International Journal of Modern Physics A, 2004 As an unstable light pure leptonic system, positronium is a very specific probe atom to test bound state QED. In contrast to ordinary QED for free leptons, the bound state QED theory is not so well understood and bound state approaches deserve highly accurate tests.
openaire +3 more sources
Isospin-breaking effects in the two-pion contribution to hadronic vacuum polarization
Journal of High Energy Physics, 2022 Isospin-breaking (IB) effects in the two-pion contribution to hadronic vacuum polarization (HVP) can be resonantly enhanced, if related to the interference of the ρ(770) and ω(782) resonances.
Gilberto Colangelo +3 more
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Radiative corrections in e+e− collisions with the BabaYaga event generator
EPJ Web of Conferences, 2017 The Monte Carlo event generator BabaYaga has been developed in the last decade for high precision simulation of QED processes (e+e− → e+e−, e+e− → μ+μ− and e+e− → γγ) at flavour factories, mainly for luminometry purposes, with an estimated theoretical ...
Carloni Calame Carlo M.
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Photon splitting corrections to soft-photon resummation
Journal of High Energy Physics, 2023 In this paper we present an algorithm to add photon-splitting corrections to the Yennie-Frautschi-Suura-style soft-photon resummation available in the Sherpa MonteCarlo event generator.
Lois Flower, Marek Schönherr
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Axial-vector transition form factors and e + e − → f 1 π + π −
Journal of High Energy Physics, 2023 We study the transition form factors (TFFs) of axial-vector mesons in the context of currently available experimental data, including new constraints from e + e − → f 1(1285)π + π − that imply stringent limits on the high-energy behavior and, for the ...
Martin Hoferichter +2 more
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Coloring mixed QCD/QED evolution
SciPost Physics, 2022 Parton showers are crucial components of high-energy physics calculations. Improving their modelling of QCD is an active research area since shower approximations are stumbling blocks for precision event generators.
Leif Gellersen, Stefan Prestel, Michael Spannowsky
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