English
Related papers

Related papers: One-Loop Amplitudes for e^+ e^- to Four Partons

200 papers

The reaction $e^+e^-$ annihilation into three jets was recently computed for massive quarks at next-to-leading order in perturbative QCD. We discuss some results of our calculation for b jets produced at the Z resonance.

High Energy Physics - Phenomenology · Physics 2011-01-25 W. Bernreuther , A. Brandenburg , P. Uwer

We calculate the one-loop QCD virtual corrections to all helicity amplitudes for parton level virtual Compton scattering processes. We include the amplitudes both on quark target process $\gamma^* q\to\gamma q$ and on gluon target process…

High Energy Physics - Phenomenology · Physics 2009-11-10 H. W. Huang , T. Morii

We present in detail a calculation of the next-to-leading order QCD corrections to the process $e^+e^-\to 3$ jets with massive quarks. To isolate the soft and collinear divergencies of the four parton matrix elements, we modify the phase…

High Energy Physics - Phenomenology · Physics 2009-10-30 Arnd Brandenburg , Peter Uwer

We compute helicity amplitudes for the one-loop QCD corrections to top-quark pair production analytically in terms of a set of uniformly transcendental master integrals. We provide corrections up to $O(\epsilon^2)$ in the dimensional…

High Energy Physics - Phenomenology · Physics 2022-06-29 Simon Badger , Matteo Becchetti , Ekta Chaubey , Robin Marzucca , Francesco Sarandrea

We compute the two-loop Quantum Chromodynamics (QCD) corrections to all partonic channels relevant for the production of an electroweak boson $V=Z,W^\pm,\gamma^*$ and a jet at hadron colliders. We consider the decay of a vector boson $V$ to…

High Energy Physics - Phenomenology · Physics 2023-06-21 Thomas Gehrmann , Petr Jakubčík , Cesare Carlo Mella , Nikolaos Syrrakos , Lorenzo Tancredi

We compute the one-loop amplitude for a Higgs boson, a quark-antiquark pair and a pair of gluons of negative helicity, i.e. for the next-to-maximally helicity violating (NMHV) case, A(H, qbar-, q+, g-, g-). The calculation is performed…

High Energy Physics - Phenomenology · Physics 2009-12-17 Simon Badger , John M. Campbell , R. Keith Ellis , Ciaran Williams

We consider one-loop amplitudes of a Higgs boson coupled to gluons in the limit of a large top quark mass. We treat the Higgs as the real part of a complex field phi that couples to the self-dual field strengths and compute the one-loop…

High Energy Physics - Phenomenology · Physics 2010-01-22 Simon Badger , E. W. Nigel Glover , Pierpaolo Mastrolia , Ciaran Williams

We review the current status of high-multiplicity double-virtual QCD corrections to processes relevant for LHC phenomenology. In particular, we discuss the recent full-color calculation of the five-parton process, whose two-loop amplitudes…

High Energy Physics - Phenomenology · Physics 2024-06-27 Giuseppe De Laurentis

This report describes the recent efforts to compute analytic formulae for the Next-to-Leading-Order (NLO) QCD corrections to Higgs plus two jet production at hadron colliders. In these calculations the Higgs boson couples to gluons via a…

High Energy Physics - Phenomenology · Physics 2014-11-20 Ciaran Williams

One- and two-jet inclusive quantities in hadron collisions have already been calculated to next-to-leading order accuracy, using both the subtraction and the cone method. Since the one-loop corrections have recently been obtained for all…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Frixione , Z. Kunszt , A. Signer

We present the analytic results of one-loop squared amplitudes for $tW$ production at a hadron collider. The calculation is performed using the method of differential equations. After renormalization, we have checked that the infrared…

High Energy Physics - Phenomenology · Physics 2022-08-30 Long-Bin Chen , Liang Dong , Hai Tao Li , Zhao Li , Jian Wang , Yefan Wang

In this work we report on a next-to-leading order calculation of WW + jet production at hadron colliders, with subsequent leptonic decays of the W-bosons included. The calculation of the one-loop contributions is performed using generalized…

High Energy Physics - Phenomenology · Physics 2015-08-05 John M. Campbell , David J. Miller , Tania Robens

We calculate the cross section for $e^+ e^-$ annihilation into three jets for massive quarks at next-to-leading order in perturbative QCD, both on and off the $Z$ resonance. Our computation allows the implementation of any jet clustering…

High Energy Physics - Phenomenology · Physics 2009-10-30 Werner Bernreuther , Arnd Brandenburg , Peter Uwer

We present recent advancements in the computation of three-loop four-particle helicity amplitudes in full-color massless QCD. In this contribution, we focus on the $gg \to \gamma\gamma$ process. We show how to obtain compact analytic…

High Energy Physics - Phenomenology · Physics 2024-10-04 Piotr Bargiela

We present analytic expressions for the one-loop QCD helicity amplitudes contributing to top-quark pair production in association with a photon or a jet at the Large Hadron Collider (LHC), evaluated through $\mathcal{O}(\epsilon^2)$ in the…

High Energy Physics - Phenomenology · Physics 2026-05-15 Souvik Bera , Colomba Brancaccio , Dhimiter Canko , Heribertus Bayu Hartanto

We compute the helicity amplitudes for the processes $gg\to Zg$ and $gg\to Z\gamma$ to two loops in massless QCD. The perturbative expansion of these processes starts only at the one-loop level, such that our results are a crucial…

High Energy Physics - Phenomenology · Physics 2023-08-21 Thomas Gehrmann , Lorenzo Tancredi , Erich Weihs

We consider the three-loop scattering amplitudes for the production of a pair of photons in quark-antiquark annihilation in Quantum Chromodynamics (QCD). We use suitably defined projectors to efficiently calculate all helicity amplitudes.…

High Energy Physics - Phenomenology · Physics 2021-03-24 Fabrizio Caola , Andreas von Manteuffel , Lorenzo Tancredi

We present the two-loop QCD helicity amplitudes for quark-gluon scattering, and for quark-antiquark annihilation into two gluons. These amplitudes are relevant for next-to-next-to-leading order corrections to (polarized) jet production at…

High Energy Physics - Phenomenology · Physics 2014-01-28 Z. Bern , A. De Freitas , L. Dixon

We compute the two-loop massless QCD corrections to the helicity amplitudes for the production of two massive vector bosons in quark-antiquark annihilation, allowing for an arbitrary virtuality of the vector bosons: $q \bar q' \to V_1V_2$.…

High Energy Physics - Phenomenology · Physics 2015-10-28 Thomas Gehrmann , Andreas von Manteuffel , Lorenzo Tancredi

We calculate the two-loop QCD corrections to $gg \to ZZ$ involving a closed top-quark loop. We present a new method to systematically construct linear combinations of Feynman integrals with a convergent parametric representation, where we…

High Energy Physics - Phenomenology · Physics 2021-06-16 Bakul Agarwal , Stephen P. Jones , Andreas von Manteuffel