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Related papers: Extending CKKW-merging to One-Loop Matrix Elements

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The matrix element method is the LHC inference method of choice for limited statistics. We present a dedicated machine learning framework, based on efficient phase-space integration, a learned acceptance and transfer function. It is based…

High Energy Physics - Phenomenology · Physics 2024-11-13 Theo Heimel , Nathan Huetsch , Ramon Winterhalder , Tilman Plehn , Anja Butter

In this article, we present a method to calculate a posteriori event weights at next-to-leading-order (NLO) QCD accuracy for a given jet event defined by the (anti-)$k_t$ algorithm relying on the conventional $2\to 1$ recombination. This is…

High Energy Physics - Phenomenology · Physics 2019-10-17 Manfred Kraus , Till Martini , Peter Uwer

We present the theory of QED x QCD resummation and its interplay with shower/matrix element matching in precision LHC physics scenarios. We illustrate the theory using single heavy gauge boson production at hadron colliders.

High Energy Physics - Phenomenology · Physics 2008-11-26 B. F. L. Ward , S. A. Yost

We consider a parametrization of the lepton mixing matrix in which the deviations from maximal atmospheric mixing and vanishing reactor mixing are obtained in terms of small corrections from the charged lepton sector. Relatively large…

High Energy Physics - Phenomenology · Physics 2012-02-17 S. Dev , Shivani Gupta , Radha Raman Gautam

We present a method of merging the exclusive LO-matched high energy resummation of High Energy Jets (HEJ) with the parton shower of Pythia which preserves the accuracy of the LO cross sections and the logarithmic accuracy of both…

High Energy Physics - Phenomenology · Physics 2023-01-23 Jeppe R. Andersen , Hitham Hassan , Sebastian Jaskiewicz

Large logarithms that arise in cross sections due to the collinear and soft singularities of QCD are traditionally treated using parton showers or analytic resummation. Parton showers provide a fully-differential description of an event but…

High Energy Physics - Phenomenology · Physics 2020-01-08 Gillian Lustermans , Andreas Papaefstathiou , Wouter J. Waalewijn

The Matrix Element Method (MEM) has proven beneficial to make maximal use of the information available in experimental data. However, so far it has mostly been used in Born approximation only. In this paper we discuss an extension to NLO…

High Energy Physics - Phenomenology · Physics 2015-11-30 Till Martini , Peter Uwer

In this work, we have modified a scenario, originally proposed by Grimus and Lavoura, in order to obtain maximal values for atmospheric mixing angle and CP violating Dirac phase of the lepton sector. To achieve this, we have employed CP and…

High Energy Physics - Phenomenology · Physics 2022-10-05 Joy Ganguly , Raghavendra Srikanth Hundi

If no new physics signals are found, in the coming years, at the Large Hadron Collider Run-2, an increase in precision of the Higgs couplings measurements will shift the dicussion to the effects of higher order corrections. In Beyond the…

High Energy Physics - Phenomenology · Physics 2017-08-02 Raul Costa , Marco O. P. Sampaio , Rui Santos

An algorithm is presented in which the Colour-Dipole Cascade Model as implemented in the Ariadne program is corrected to match the fixed order tree-level matrix elements for e+e- -> n jets. The result is a full parton level generator for…

High Energy Physics - Phenomenology · Physics 2009-11-07 Leif Lonnblad

Recent work on leading order multiparton calculations for hadronic collisions is reviewed, with special emphasis on the ALPGEN event generator. Some problems connected with the interface of the partonic events generated via matrix elements…

High Energy Physics - Phenomenology · Physics 2011-09-13 Fulvio Piccinini

We rewrite the Bagger-Lambert action for any Lie 3-algebra as a standard Chern- Simons action coupled to matter. We use this action to compute self-energies and vertex corrections at one-loop order. Non-renormalization of the coupling…

High Energy Physics - Theory · Physics 2008-11-26 Andreas Gustavsson

We review recent developments in the calculation of QCD loop amplitudes with several external legs, and their application to next-to-leading order jet production cross-sections. When a number of calculational tools are combined together ---…

High Energy Physics - Phenomenology · Physics 2007-05-23 Z. Bern , L. Dixon , D. A. Kosower , A. Signer

We extend the multi-purpose Monte-Carlo event generator Sherpa to include processes in deeply inelastic lepton-nucleon scattering. Hadronic final states in this kinematical setting are characterised by the presence of multiple kinematical…

High Energy Physics - Phenomenology · Physics 2015-09-22 Tancredi Carli , Thomas Gehrmann , Stefan Höche

We implement a one-loop analysis of the $\rho$ parameter in the Left Right Twin Higgs model, including the logarithmically enhanced contributions from both fermion and scalar loops. Numerical results show that the one-loop contributions are…

High Energy Physics - Phenomenology · Physics 2007-10-16 Dong-Won Jung , Jae Yong Lee

We compute one-loop QCD corrections to the triple differential width of the inclusive decay $\bar{B} \to X_c \ell \bar{\nu}_\ell$ including contributions from all relevant dimension-six operators in the Weak Effective Theory (WET), at…

High Energy Physics - Phenomenology · Physics 2026-01-23 Alexandre Carvunis , Gael Finauri

We study 3-jet event topologies in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 13 {\rm\ TeV}$ in a configuration, where one jet is present in the central pseudorapidity region ($|\eta| < 2.0$) while two other jets are…

High Energy Physics - Phenomenology · Physics 2020-08-26 H. Van Haevermaet , A. Van Hameren , P. Kotko , K. Kutak , P. Van Mechelen

KKMChh is a precision Monte Carlo program for photonic and electroweak radiative corrections to hadron scattering, implementing the amplitude-level exponentiation originally developed for electron-positron scattering at the quark level,…

High Energy Physics - Phenomenology · Physics 2025-01-06 Scott A. Yost , B. F. L. Ward , Zbigniew Wąs

Single top-quark production offers a unique laboratory for precision tests of the Standard Model and searches of possible extensions. Furthermore, assuming the Standard Model, single top-quark production can be used to determine top-quark…

High Energy Physics - Phenomenology · Physics 2018-01-15 Till Martini , Peter Uwer