English
Related papers

Related papers: Higgs Amplitudes From Twistor Inspired Methods

200 papers

We show how the holomorphic anomaly found in hep-th/0409245 can be used to efficiently compute certain classes of unitarity cuts of one-loop N=4 amplitudes of gluons. These classes include all cuts of n-gluon one-loop MHV amplitudes and of…

High Energy Physics - Theory · Physics 2007-05-23 Freddy Cachazo

In this work, we review and clarify computational issues about the W-gauge boson one-loop contribution to the H -> gamma gamma decay amplitude, in the unitary gauge and in the Standard Model. We find that highly divergent integrals depend…

High Energy Physics - Phenomenology · Physics 2013-05-20 Athanasios Dedes , Kristaq Suxho

We apply the on-shell tree-level recursion relations of Britto, Cachazo, Feng and Witten to a variety of processes involving internal and external massive particles with spin. We show how to construct multi-vector boson currents where one…

High Energy Physics - Theory · Physics 2009-11-11 S. D. Badger , E. W. N. Glover , Valentin V. Khoze

We use supersymmetric Ward identities to relate multi-gluon helicity amplitudes involving a pair of massive quarks to amplitudes with massive scalars. This allows to use the recent results for scalar amplitudes with an arbitrary number of…

High Energy Physics - Theory · Physics 2009-11-11 Christian Schwinn , Stefan Weinzierl

We propose a novel method for the treatment of top-quark mass effects in the production of $H^{(*)}$, $HH$, $HZ$ and $ZZ$ final states in gluon fusion. We show that it is possible to reconstruct the full top-quark mass dependence of the…

High Energy Physics - Phenomenology · Physics 2018-03-07 Ramona Gröber , Andreas Maier , Thomas Rauh

We present a complete set of 4-point amplitudes in the constructive Standard Model at tree level. Any 4-point amplitude can be obtained from the results presented here by a suitable choice of masses, a permutation of the particles (by…

High Energy Physics - Phenomenology · Physics 2024-06-18 Neil Christensen

We use on-shell methods to calculate tree-level effective field theory (EFT) amplitudes, with no reference to the EFT operators. Lorentz symmetry, unitarity and Bose statistics determine the allowed kinematical structures. As a by-product,…

High Energy Physics - Phenomenology · Physics 2019-03-27 Yael Shadmi , Yaniv Weiss

We present new recursion relations for tree amplitudes in gauge theory that give very compact formulas. Our relations give any tree amplitude as a sum over terms constructed from products of two amplitudes of fewer particles multiplied by a…

High Energy Physics - Theory · Physics 2008-11-26 Ruth Britto , Freddy Cachazo , Bo Feng

The phenomenology of unstable particles, including searches and exclusion limits at the LHC, depends significantly on its lineshape. When the width of the resonance is large with respect to its mass, off-shell effects become relevant and…

High Energy Physics - Phenomenology · Physics 2013-03-27 Diogo Buarque Franzosi , Fabio Maltoni , Cen Zhang

We study the scattering of longitudinally polarized W bosons in extensions of the Standard Model where anomalous Higgs couplings to gauge sector and higher order O(p^4) operators are considered. These new couplings with respect to the…

High Energy Physics - Phenomenology · Physics 2014-08-06 Domenec Espriu , Federico Mescia

We compute the Higgs plus two-quark and one-gluon amplitudes ($H \rightarrow q \bar{q} g$) and Higgs plus three-gluon amplitudes ($H \rightarrow 3g$) in the Higgs effective theory with a general class of operators. By changing the quadratic…

High Energy Physics - Theory · Physics 2020-08-26 Qingjun Jin , Gang Yang

We explore the new physics reach for the off-shell Higgs boson measurement in the ${pp \to H^* \rightarrow Z(\ell^{+}\ell^{-})Z(\nu\bar{\nu})}$ channel at the high-luminosity LHC. The new physics sensitivity is parametrized in terms of the…

High Energy Physics - Phenomenology · Physics 2021-05-05 Dorival Gonçalves , Tao Han , Sze Ching Iris Leung , Han Qin

It is shown how tree-level multi-gluon helicity amplitudes with an arbitrary number of off-shell external gluons can be calculated via BCFW recursion. Compact expressions for helicity amplitudes for scattering processes of three and four…

High Energy Physics - Phenomenology · Physics 2015-06-19 A. van Hameren

We illustrate the use of recursion relations in the computation of certain one-loop helicity amplitudes containing an arbitrary number of gauge bosons. After a brief review of the recursion relations themselves, we discuss the resolution of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gregory Mahlon

We combine the six-dimensional helicity formalism of Cheung and O'Connell with D-dimensional generalized unitarity to obtain a new formalism for computing one-loop amplitudes in dimensionally regularized QCD. With this procedure, we…

High Energy Physics - Phenomenology · Physics 2013-05-29 Scott Davies

An important ingredient for the calculation of Higgs boson properties in the infinite top quark mass limit is the knowledge of the effective coupling between the Higgs bosons and gluons, i.e. the Wilson coefficients $C_H$ and $C_{HH}$ for…

High Energy Physics - Phenomenology · Physics 2018-12-05 Marvin Gerlach , Florian Herren , Matthias Steinhauser

In this paper, we investigate how the LHC data limit the Higgs-related couplings in the effective description of a strongly interacting extension of the Standard model. The Higgs boson is introduced as a scalar composite state and it is…

High Energy Physics - Phenomenology · Physics 2016-12-12 Mikulas Gintner , Josef Juran

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

Using the recently introduced recursion relations with covariant massive-massless shift, we study tree-level scattering amplitudes involving a pair of massive vector bosons and an arbitrary number of gluons in the massive spinor-helicity…

High Energy Physics - Theory · Physics 2022-08-24 Sourav Ballav , Arkajyoti Manna

We obtain for the first time the two-loop amplitudes for Higgs plus three gluons in Higgs effective field theory including dimension-seven operators. This provides the S-matrix elements for the top mass corrections for Higgs plus a jet…

High Energy Physics - Theory · Physics 2018-09-11 Qingjun Jin , Gang Yang