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Author (up) Aguilera-Verdugo, J.J.; Hernandez-Pinto, R.J.; Rodrigo, G.; Sborlini, G.F.R.; Torres Bobadilla, W.J.
Title Mathematical properties of nested residues and their application to multi-loop scattering amplitudes Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 112 - 42pp
Keywords NLO Computations; QCD Phenomenology
Abstract The computation of multi-loop multi-leg scattering amplitudes plays a key role to improve the precision of theoretical predictions for particle physics at high-energy colliders. In this work, we focus on the mathematical properties of the novel integrand-level representation of Feynman integrals, which is based on the Loop-Tree Duality (LTD). We explore the behaviour of the multi-loop iterated residues and explicitly show, by developing a general compact and elegant proof, that contributions associated to displaced poles are cancelled out. The remaining residues, called nested residues as originally introduced in ref. [1], encode the relevant physical information and are naturally mapped onto physical configurations associated to nondisjoint on-shell states. By going further on the mathematical structure of the nested residues, we prove that unphysical singularities vanish, and show how the final expressions can be written by using only causal denominators. In this way, we provide a mathematical proof for the all-loop formulae presented in ref. [2].
Address [Jesus Aguilera-Verdugo, J.; Rodrigo, German; Sborlini, German F. R.; Torres Bobadilla, William J.] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient, E-46980 Valencia, Spain, Email: jesus.aguilera@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000620526300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4726
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Author (up) Alioli, S.; Fuster, J.; Garzelli, M.V.; Gavardi, A.; Irles, A.; Melini, D.; Moch, S.O.; Uwer, P.; Voss, K.
Title Phenomenology of t(t)over-barj plus X production at the LHC Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 146 - 63pp
Keywords Specific QCD Phenomenology; Top Quark
Abstract We present phenomenological results for t (t) over barj + X production at the Large Hadron Collider, of interest for designing forthcoming experimental analyses of this process. We focus on those cases where the t (t) over barj + X process is considered as a signal. We discuss present theoretical uncertainties and the dependence on relevant input parameters entering the computation. For the R. distribution, which depends on the invariant mass of the t (t) over barj-system, we present reference predictions in the on-shell, (MS) over bar and MSR top-quark mass renormalization schemes, applying the latter scheme to this process for the first time. Our conclusions are particularly interesting for those analyses aiming at extracting the topquark mass from cross-section measurements.
Address [Alioli, Simone; Gavardi, Alessandro] Univ Milano Bicocca, Dipartimento Fis G Occhialini, Piazza Sci 3, I-20126 Bicocca, Italy, Email: simone.alioli@unimib.it;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000801110800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5236
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Author (up) Alvarez, M.; Cantero, J.; Czakon, M.; Llorente, J.; Mitov, A.; Poncelet, R.
Title NNLO QCD corrections to event shapes at the LHC Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 129 - 24pp
Keywords Higher-Order Perturbative Calculations; Specific QCD Phenomenology
Abstract 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 next-to-leading order predictions. The theory uncertainty at NNLO is comparable to, or slightly larger than, existing measurements. Except for narrow kinematical ranges where all-order resummation becomes important, the NNLO predictions for the event shapes considered in the present work are reliable. As a prime application of the results derived in this work we provide a detailed investigation of the prospects for the precision determination of the strong coupling constant and its running through TeV scales from LHC data.
Address [Czakon, Michal] Rhein Westfal TH Aachen, Inst Theoret Teilchenphys & Kosmol, D-52056 Aachen, Germany, Email: manuel.alvarez.estevez@cern.ch;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000992064600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5560
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Author (up) Ayala, C.; Cvetic, G.; Kogerler, R.
Title Lattice-motivated holomorphic nearly perturbative QCD Type Journal Article
Year 2017 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 44 Issue 7 Pages 075001 - 30pp
Keywords perturbative QCD; lattice QCD; QCD phenomenology; resummation
Abstract Newer lattice results indicate that, in the Landau gauge at low spacelike momenta, the gluon propagator and the ghost dressing function are finite non-zero. This leads to a definition of the QCD running coupling, in a specific scheme, that goes to zero at low spacelike momenta. We construct a running coupling which fulfills these conditions, and at the same time reproduces to a high precision the perturbative behavior at high momenta. The coupling is constructed in such a way that it reflects qualitatively correctly the holomorphic (analytic) behavior of spacelike observables in the complex plane of the squared momenta, as dictated by the general principles of quantum field theories. Further, we require the coupling to reproduce correctly the nonstrange semihadronic decay rate of tau lepton which is the best measured low-momentum QCD observable with small higher-twist effects. Subsequent application of the Borel sum rules to the V + A spectral functions of tau lepton decays, as measured by OPAL Collaboration, determines the values of the gluon condensate and of the V + A six-dimensional condensate, and reproduces the data to a significantly higher precision than the usual (MS) over bar running coupling.
Address [Ayala, Cesar] Univ Valencia, Dept Theoret Phys, E-46100 Valencia, Spain, Email: Gorazd.Cvetic@usm.cl
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:000402509800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3167
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Author (up) Bierenbaum, I.; Buchta, S.; Draggiotis, P.; Malamos, I.; Rodrigo, G.
Title Tree-loop duality relation beyond single poles Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 025 - 24pp
Keywords QCD Phenomenology; NLO Computations
Abstract We develop the Tree-Loop Duality Relation for two- and three-loop integrals with multiple identical propagators (multiple poles). This is the extension of the Duality Relation for single poles and multi-loop integrals derived in previous publications. We prove a generalization of the formula for single poles to multiple poles and we develop a strategy for dealing with higher-order pole integrals by reducing them to single pole integrals using Integration By Parts.
Address Univ Hamburg, Inst Theoret Phys 2, D-22761 Hamburg, Germany, Email: isabella.bierenbaum@desy.de;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000317521200025 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1418
Permanent link to this record