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Related papers: One-loop phi-MHV amplitudes using the unitarity bo…

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We compute the two-loop massless QCD corrections to the four-point amplitude $g+g \rightarrow H+H$ resulting from effective operator insertions that describe the interaction of a Higgs boson with gluons in the infinite top quark mass limit.…

High Energy Physics - Phenomenology · Physics 2018-11-30 Pulak Banerjee , Sophia Borowka , Prasanna K. Dhani , Thomas Gehrmann , V. Ravindran

We perform a model independent analysis of the helicity amplitudes at high energy for all the $2\to2$ scattering processes involving gauge and Higgs bosons in the presence of anomalous $WWV$, $WWVV$, $VVH$, $VVHH$ ($V\equiv Z,\gamma$ and…

High Energy Physics - Phenomenology · Physics 2016-03-23 Mamta Dahiya , Sukanta Dutta , Rashidul Islam

The $H\to gg$ amplitude relevant for Higgs production via gluon fusion is computed in the four-dimensional helicity scheme (FDH) and in dimensional reduction (DRED) at the two-loop level. The required renormalization is developed and…

High Energy Physics - Phenomenology · Physics 2015-09-30 A. Broggio , Ch. Gnendiger , A. Signer , D. Stöckinger , A. Visconti

We derive the scale of unitarity violation from the geometry of Effective Field Theory (EFT) extensions of the Standard Model Higgs sector. The high-energy behavior of amplitudes with more than four scalar legs depends on derivatives of…

High Energy Physics - Phenomenology · Physics 2021-12-22 Timothy Cohen , Nathaniel Craig , Xiaochuan Lu , Dave Sutherland

We calculate the three-loop matching coefficient $C_{HH}$, required for a consistent description of Higgs boson pair production in gluon fusion through next-to-next-to-leading order QCD in the heavy top quark approximation. We also compute…

High Energy Physics - Phenomenology · Physics 2015-06-22 Jonathan Grigo , Kirill Melnikov , Matthias Steinhauser

We present the one-loop helicity amplitudes for processes involving a vector boson V (V=W,Z, or gamma^*) and four massless quarks, 0 to V q-bar q Q-bar Q, where V couples to a massless lepton pair. These amplitudes are required for…

High Energy Physics - Phenomenology · Physics 2014-11-17 Z. Bern , L. Dixon , D. A. Kosower , S. Weinzierl

We present advances in the development of the numerical unitarity method for the computation of multi-loop amplitudes in QCD. As an application, we show results for all the leading-color two-loop five-gluon helicity amplitudes. The…

High Energy Physics - Phenomenology · Physics 2018-07-26 Samuel Abreu , Fernando Febres Cordero , Harald Ita , Ben Page , Mao Zeng

Standard-Model Higgs bosons are dominantly produced via the gluon-fusion mechanism $gg \to H$ at the LHC, i.e. in a loop-mediated process with top loops providing the dominant contribution. For the measured Higgs boson mass of $\sim 125$…

High Energy Physics - Phenomenology · Physics 2016-11-03 Michael Spira

We compute all two-loop master integrals which are required for the evaluation of next-to-leading order QCD corrections in Higgs boson production via gluon fusion. Many two-loop amplitudes for 2 -> 1 processes in the Standard Model and…

High Energy Physics - Phenomenology · Physics 2010-10-27 Charalampos Anastasiou , Stefan Beerli , Stefan Bucherer , Alejandro Daleo , Zoltan Kunszt

We propose that loop integrals with internal heavy particles can be evaluated by expanding in the limit of small external masses. This provides a systematically improvable approximation to the integrals in the entire phase space, and works…

High Energy Physics - Phenomenology · Physics 2019-02-05 Xiaofeng Xu , Li Lin Yang

We compute the two-loop helicity amplitudes for the scattering of five gluons, including all contributions beyond the leading-color approximation. The analytic expressions are represented as linear combinations of transcendental functions…

High Energy Physics - Phenomenology · Physics 2024-05-15 Giuseppe De Laurentis , Harald Ita , Maximillian Klinkert , Vasily Sotnikov

Effective field theories are useful tools to search for physics beyond the Standard Model (SM). However, effective theories can lead to non-unitary behavior with fastly growing amplitudes. This unphysical behavior may lead to large…

High Energy Physics - Phenomenology · Physics 2022-01-19 Iñigo Asiáin , Domènec Espriu , Federico Mescia

We present for the first time the second-order corrections of pseudo-scalar($A$) Higgs decay to three parton to higher orders in the dimensional regulator. We compute the one and two-loop amplitudes for processes, $A\to ggg$ and $A\to…

High Energy Physics - Phenomenology · Physics 2026-01-30 Pulak Banerjee , Chinmoy Dey , M. C. Kumar , V. Ravindran

We present analytic results for the one-loop corrections of the helicity amplitudes of the QCD five-parton subprocesses involving four quarks and one gluon obtained with a standard Feynman diagram calculation using dimensional reduction.

High Energy Physics - Phenomenology · Physics 2009-10-28 Zoltan Kunszt , Adrian Signer , Zoltan Trocsanyi

We obtain the two-loop QCD corrections to the Higgs plus three-parton amplitudes with dimension-seven operators in Higgs effective field theory. This provides the two-loop S-matrix elements for Higgs plus one-jet production at the LHC with…

High Energy Physics - Phenomenology · Physics 2020-03-18 Qingjun Jin , Gang Yang

Real emission corrections to Higgs production via gluon fusion, at order alpha_s^4, lead to a Higgs plus two-jet final state. We present the calculation of these scattering amplitudes, as induced by top-quark triangle-, box- and…

High Energy Physics - Phenomenology · Physics 2011-05-05 V. Del Duca , W. Kilgore , C. Oleari , C. Schmidt , D. Zeppenfeld

We describe techniques that simplify the calculation of one-loop QCD amplitudes with many external legs, which are needed for next-to-leading-order (NLO) corrections to multi-jet processes. The constraints imposed by perturbative unitarity,…

High Energy Physics - Phenomenology · Physics 2010-11-15 Z. Bern , L. Dixon , D. C. Dunbar , D. A. Kosower

The Higgs boson effective self-couplings $\lambda_{hhh}$ and $\lambda_{HHH}$ are calculated in the framework of the Minimal Supersymmetric Standard Model (MSSM) for the complete set of one-loop diagrams with one of the Higgs bosons…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. V. Dolgopolov , Yu. P. Philippov

We review the recently developed bootstrap method for the computation of high-multiplicity QCD amplitudes at one loop. We illustrate the general algorithm step by step with a six-point example. The method combines (generalized) unitarity…

High Energy Physics - Phenomenology · Physics 2008-11-26 Carola F. Berger

We calculate the order O(alpha^2 alpha_s^3) interference effect between the gluon fusion and weak boson fusion processes allowed at the one-loop level in Higgs boson plus 2 jet production at the LHC. The corresponding one-loop amplitudes,…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. R. Andersen , T. Binoth , G. Heinrich , J. M. Smillie