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The complete two-loop electroweak fermionic corrections to the effective leptonic weak mixing angle, sin^2(theta_eff), are now available. Here we shortly present the methods applied and illustrate the implications on indirect prediction for…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Awramik , M. Czakon , A. Freitas , G. Weiglein

A method of computing two-loop fermionic contributions to the width of a heavy quark is described. An analytical formula for this effect in the limit of mass of the quark much larger than the decay products is obtained for the first time.…

High Energy Physics - Phenomenology · Physics 2011-03-02 Andrzej Czarnecki

We compute the dominant logarithmically enhanced two-loop electroweak corrections to the electron-positron scattering differential cross section in the high energy limit for large scattering angles. Depending on the scattering angle and…

High Energy Physics - Phenomenology · Physics 2011-12-12 A. A. Penin , G. Ryan

We present a determination of a new class of three-loop Feynman diagrams describing heavy-to-light transitions. We apply it to find the O(alpha_s^2) corrections to the top quark decay t -> bW and to the distribution of lepton invariant mass…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ian Blokland , Andrzej Czarnecki , Maciej Slusarczyk , Fyodor Tkachov

The effect of threshold singularities induced by unstable particles on two-loop observables is investigated and it is shown how to cure them working in the complex-mass scheme. The impact on radiative corrections around thresholds is…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Actis , G. Passarino , C. Sturm , S. Uccirati

In the asymptotic limit $Q^2 \gg m^2$, the non-power corrections to the heavy flavour Wilson coefficients in deep--inelastic scattering are given in terms of massless Wilson coeffcients and massive operator matrix elements. We start…

High Energy Physics - Phenomenology · Physics 2008-12-19 I. Bierenbaum , J. Blümlein , S. Klein

Electroweak precision observables allow stringent tests of the Standard Model at the quantum level and imply interesting bounds on the mass of the Higgs boson through higher-order loop effects. Very significant constraints come especially…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Freitas , M. Awramik , M. Czakon

The two-loop corrections to the electroweak gauge bosons quartic couplings growing quadratically with the Higgs boson mass are calculated in the Standard Model in the limit of large Higgs mass. The corrections to WWWW, WWZZ and ZZZZ…

High Energy Physics - Phenomenology · Physics 2009-10-30 V. Borodulin , G. Jikia

Recent higher-order results for the prediction of the W-boson mass, M_W, within the Standard Model are reviewed and an estimate of the remaining theoretical uncertainties of the electroweak precision observables is given. An updated version…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ayres Freitas , Sven Heinemeyer , Georg Weiglein

The two-loop O(g^4 mt^2/mw^2) corrections are incorporated in the theoretical calculation of MW, sin^2 theta_MSbar(MZ), and sin^2 theta_eff, as functions of MH. The analysis is carried out in a previously proposed MSbar formulation and two…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Degrassi , P. Gambino , A. Sirlin

We present the currently most precise predictions for the $W$-boson mass and the leptonic effective mixing angle $\sin^2\theta_{\text{eff}}$ in the aligned Two-Higgs-Doublet Model. The evaluation includes the full one-loop result, all known…

High Energy Physics - Phenomenology · Physics 2022-12-21 Stephan Hessenberger , Wolfgang Hollik

Theoretical uncertainties affecting electroweak observables are reviewed and the relevance of two-loop electroweak radiative corrections for the precision tests of the Standard Model is discussed.

High Energy Physics - Phenomenology · Physics 2008-02-03 G. Degrassi , S. Fanchiotti , F. Feruglio , P. Gambino , A. Vicini

We present a computation of the O(at*as + at^2) two--loop corrections to the MSSM Higgs masses. An appropriate use of the effective potential approach allows us to obtain simple analytical formulae, valid for arbitrary values of mA and of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Pietro Slavich

Radiative corrections to both perturbative and non-perturbative contributions are added to existing calculations of the Isgur-Wise function $\xi_{IW}$. To this end, we develop a method for calculating two-loop integrals in the heavy quark…

High Energy Physics - Phenomenology · Physics 2010-11-01 E. Bagan , P. Ball , P. Gosdzinsky

We identify a novel next-to-leading order renormalization effect in the dimension-six SMEFT with direct phenomenological impact. The Higgs-Yukawa operator that modifies the top-Higgs coupling $\kappa_t$ induces a shift in the $ W $ mass at…

High Energy Physics - Phenomenology · Physics 2026-05-01 Lukas Born , Admir Greljo , Anders Eller Thomsen

The physics impact of a precise determination of the top-quark mass, m_t, at the Linear Collider (LC) is discussed, and the results are compared with the prospective accuracy at the LHC. The importance of a precise knowledge of m_t for…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Heinemeyer , S. Kraml , W. Porod , G. Weiglein

Future lepton colliders will provide a powerful tool for making precision experiments at energies that will range typically between 500 GeV and 2 TeV. At such high energies, one loop electroweak corrections are bigger than one could naively…

High Energy Physics - Phenomenology · Physics 2016-09-06 Paolo Ciafaloni

In most of the mass range encompassed by the limits from the direct search and the electroweak precision tests, the Higgs boson of the standard model preferably decays to bottom quarks. We present, in analytic form, the dominant two-loop…

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

Recent results of two-loop contributions to the muon (g-2) in the Standard Model and its supersymmetric extension are presented. In the SM the EW contributions are fixed according to the Higgs boson mass measured at LHC. In the MSSM we…

High Energy Physics - Phenomenology · Physics 2014-07-29 Helvecio G. Fargnoli , Christoph Gnendiger , Sebastian Paßehr , Dominik Stöckinger , Hyejung Stöckinger-Kim

The selfcoupling of the Higgs field grows with the mass of the Higgs particle and induces potentially large radiative corrections in the electroweak model. The technical aspects of performing multiloop calculations in the massive case are…

High Energy Physics - Phenomenology · Physics 2014-11-17 Adrian Ghinculov