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Related papers: Two-loop Calculations in the MSSM with FeynArts

200 papers

In this paper we study the calculation of multiloop Feynman integrals that cannot be expressed in terms of multiple polylogarithms. We show in detail how certain types of two- and three-point functions at two loops, which appear in the…

High Energy Physics - Phenomenology · Physics 2019-06-26 Johannes Broedel , Claude Duhr , Falko Dulat , Brenda Penante , Lorenzo Tancredi

The higher-order corrections become increasingly important with experiments reaching sub-percent level of uncertainty as they look for physics beyond the Standard Model. Our goal is to address the full set of two-loop electroweak…

High Energy Physics - Theory · Physics 2018-11-12 A. Aleksejevs

Using two different approaches, we perform updated and detailed calculations of the complete one-loop (Next-to-Leading Order (NLO)) set of electroweak radiative corrections to the parity violating e- e- -> e- e- (gamma) scattering…

High Energy Physics - Phenomenology · Physics 2011-08-18 A. Aleksejevs , S. Barkanova , A. Ilyichev , Y. Kolomensky , V. Zykunov

Using the parallel/orthogonal space method, we calculate the planar two-loop three-point diagram and two rotated reduced planar two-loop three-point diagrams. Together with the crossed topology, these diagrams are the most complicated ones…

High Energy Physics - Phenomenology · Physics 2009-01-07 Stefan Groote , Markus M. Knodel

We introduce techniques to treat numerically Mellin-Barnes integrals in physical regions, which arise in the need of the computation of Feynman integrals for the electroweak two-loop corrections to the pseudo observables at the Z-boson…

High Energy Physics - Phenomenology · Physics 2018-10-11 Johann Usovitsch , Ievgen Dubovyk , Tord Riemann

The current status of the theoretical predictions for the electroweak precision observables M_W, sin^2_theta_eff and m_h within the MSSM is briefly reviewed. The impact of recent electroweak two-loop results to the quantity Delta_rho is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sven Heinemeyer , Georg Weiglein

The calculation of electroweak precision observables in the MSSM is reviewed. The description of the 1997 data and the results of updated global fits are discussed in comparison with the Standard Model.

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Hollik

This article describes the latest versions of the Mathematica packages FeynArts, FormCalc, and LoopTools for the generation and evaluation of one-loop diagrams.

High Energy Physics - Phenomenology · Physics 2011-04-20 T. Hahn

We present a method for reducing general two-loop self-energies to standard scalar integrals in massive gauge theories with special emphasis on the electroweak Standard Model. It includes the tensor integral reduction for all two-loop…

High Energy Physics - Phenomenology · Physics 2009-10-22 G. Weiglein , R. Scharf , M. Böhm

We calculate the complete O(alpha) electroweak radiative corrections to e+e- --> WW --> 4f in the electroweak Standard Model in the double-pole approximation. We give analytical results for the non-factorizable virtual corrections and…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , S. Dittmaier , M. Roth , D. Wackeroth

To match the expected experimental precision at future linear colliders, improved theoretical predictions beyond next-to-leading order are required. At the anticipated energy scale of sqrt(s)=1 TeV the electroweak virtual corrections are…

High Energy Physics - Phenomenology · Physics 2009-10-31 W. Beenakker , A. Werthenbach

We propose a framework for calculating two-loop Feynman diagrams which appear within a renormalizable theory in the general mass case and at finite external momenta. Our approach is a combination of analytical results and of high accuracy…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. Ghinculov , Y. -P. Yao

We present the electroweak corrections for the production of a photon pair through gluon fusion, focusing on the contribution from the first two generations of quarks. The two-loop amplitude is calculated using a series of projection…

High Energy Physics - Phenomenology · Physics 2025-12-09 Gabriele Fiore , Ciaran Williams

The Minimal supersymmetric extension of the Standard Model (MSSM) with light stops, charginos or pseudoscalar Higgs bosons has been suggested as an explanation of the too high value of the branching ratio of the Z0 boson into b quarks (Rb…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. de Boer , A. Dabelstein , W. Hollik , W. Moesle , U. Schwickerath

Three programs are presented for automatically generating and calculating Feynman diagrams: the diagrams are generated with FeynArts, algebraically simplified with FormCalc, and finally evaluated numerically using the LoopTools package. The…

High Energy Physics - Phenomenology · Physics 2011-04-15 T. Hahn

Using the asymptotic-expansion technique, we compute the dominant two-loop electroweak corrections, of O(G_F m_t^2), to production and decay via a pair of photons or gluons of the CP-odd Higgs boson A^0 in a two-Higgs-doublet model with…

High Energy Physics - Phenomenology · Physics 2008-11-26 Joachim Brod , Frank Fugel , Bernd A. Kniehl

Recently, the calculation of fermionic electroweak two-loop corrections to the total width of the Z boson and hadronic Z-peak cross-section in the Standard Model has been presented in arXiv:1310.2256, where "fermionic" refers to diagrams…

High Energy Physics - Phenomenology · Physics 2020-12-24 A. Freitas

In this article we compute the two-loop SQCD corrections to Higgs-quark-quark couplings in the generic MSSM generated by diagrams involving squarks and gluinos. We give analytic results for the two-loop contributions in the limit of…

High Energy Physics - Phenomenology · Physics 2015-06-11 Andreas Crivellin , Christoph Greub

In the Minimal Supersymmetric Standard Model (MSSM) we incorporate the Higgs-boson propagator corrections, evaluated up to two-loop order, into the prediction of $\Gamma$(h -> ff) and BR(h -> ff) for f = b, c, $\tau$. The propagator…

High Energy Physics - Phenomenology · Physics 2011-09-13 S. Heinemeyer , W. Hollik , G. Weiglein

The one-loop corrections to the weak mixing angle $\sin^2\theta_{eff}^b$ derived from the $Z{\bar b}b$ vertex, are known since 1985. It took another 30 years to calculate the complete electroweak two-loop corrections to…

High Energy Physics - Phenomenology · Physics 2016-11-08 I. Dubovyk , A. Freitas , J. Gluza , T. Riemann , J. Usovitsch