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Related papers: Two-loop electroweak contributions to $\Delta r$

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The leading electroweak MSSM two-loop corrections to the electroweak precision observables are calculated. They are obtained by evaluating the two-loop O(\alpha_t^2), O(\alpha_t \alpha_b), O(\alpha_b^2) contributions to the quantity…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Heinemeyer , G. Weiglein

In this paper we consider mixed two-loop electroweak corrections to the top quark propagator in the Standard Model. In particular, we compute the on-shell renormalization constant for the mass and wave function, which constitute building…

High Energy Physics - Phenomenology · Physics 2011-01-13 D. Eiras , M. Steinhauser

We calculate the two-loop QCD correction to the scalar quark contributions to the electroweak gauge-boson self-energies at zero momentum-transfer in the supersymmetric extension of the Standard Model. We then derive the $O(\alpha_s)$…

High Energy Physics - Phenomenology · Physics 2009-07-09 A. Djouadi , P. Gambino , S. Heinemeyer , W. Hollik , C. Jünger , G. Weiglein

We study the scheme dependence of the two-loop expression for the $\rho$-parameter of the Standard Model in the heavy $t$-quark mass limit $m_{t} \gg m_{w}$. In the $\ms$-scheme the two-loop electroweak correction to the ${\cal…

High Energy Physics - Phenomenology · Physics 2009-12-30 A. I. Bochkarev , R. S. Willey

Improved predictions for the Z-boson decay width and the hadronic Z-peak cross-section within the Standard Model are presented, based on a complete calculation of electroweak two-loop corrections with closed fermion loops. Compared to…

High Energy Physics - Phenomenology · Physics 2014-01-24 A. Freitas

The dominant electroweak two-loop corrections to the precision observables M_W and s_w^eff are calculated in the MSSM. They are obtained by evaluating the two-loop Yukawa contributions of O(alpha_t^2), O(alpha_t alpha_b), O(alpha_b^2) to…

High Energy Physics - Phenomenology · Physics 2009-11-11 J. Haestier , S. Heinemeyer , D. Stöckinger , G. Weiglein

The leading electroweak MSSM two-loop corrections to the $\rho$-parameter are calculated. They are obtained by evaluating the two-loop self-energies of the Z and the W boson at O(Gf^2 m_t^4) in the limit of heavy scalar quarks. A very…

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

We study the relationship between the $\overline{\mathrm{MS}}$ Yukawa coupling and the pole mass for the bottom and top quarks at the two-loop electroweak order ${\cal O}(\alpha^2)$ in the gaugeless limit of the standard model. We also…

High Energy Physics - Phenomenology · Physics 2015-05-06 Bernd A. Kniehl , Oleg L. Veretin

Measurements of electroweak precision observables at future electron-positron colliders, such as the CEPC, FCC-ee, and ILC, will be sensitive to physics at multi-TeV scales. To achieve this sensitivity, precise predictions for the Standard…

High Energy Physics - Phenomenology · Physics 2021-04-07 Lisong Chen , Ayres Freitas

The present status of higher-order results in the electroweak theory is summarised, with particular emphasis on recent two-loop results for the prediction of the W-boson mass in the Standard Model and leading three-loop corrections to the…

High Energy Physics - Phenomenology · Physics 2011-07-19 G. Weiglein

The bosonic two-loop electroweak radiative corrections to the muon's anomalous magnetic moment, $a_\mu\equiv (g_\mu-2)/2$, are presented. We find $\Delta a_\mu^{\rm EW}({\rm 2\,loop\, bosonic})/ a_\mu^{\rm EW}({\rm 1\,loop})\approx…

High Energy Physics - Phenomenology · Physics 2014-11-17 Andrzej Czarnecki , Bernd Krause , William J. Marciano

The radiatively-induced splitting of masses in electroweak multiplets is relevant for both collider phenomenology and dark matter. Precision two-loop corrections of $\mathcal{O}$(MeV) to the triplet mass splitting in the wino limit of the…

High Energy Physics - Phenomenology · Physics 2018-04-03 James McKay , Pat Scott

We consider two-loop leading and next-to-leading logarithmic virtual corrections to arbitrary processes with external massless fermions in the electroweak Standard Model at energies well above the electroweak scale. Using the…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , B. Jantzen , S. Pozzorini

The QCD corrections to electroweak parameters depend on the renormalization scheme and scales used to define the top-quark mass. We analyze these dependences for the W-boson mass predicted via Delta r to O(alpha alpha_s) and O(alpha…

High Energy Physics - Phenomenology · Physics 2015-06-25 B. 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

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

In the supersymmetric extension of the Standard Model we derive the two-loop QCD corrections to the scalar quark contributions to the electroweak precision observables entering via the rho parameter. A very compact expression is derived for…

High Energy Physics - Phenomenology · Physics 2009-07-09 A. Djouadi , P. Gambino , S. Heinemeyer , W. Hollik , C. Jünger , G. Weiglein

In this article two-loop QED corrections to the muon decay and corrections of order $\alpha_s^2$ to the semileptonic decay of the bottom quark are considered. We compute the imaginary part of the four-loop diagrams contributing to the…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Steinhauser , T. Seidensticker

We have calculated the fermion contributions to the shift of the position of the poles of the massive gauge boson propagators at two-loop order in the Standard Model. Together with the bosonic contributions calculated previously the full…

High Energy Physics - Phenomenology · Physics 2009-11-07 F. Jegerlehner , M. Yu. Kalmykov , O. Veretin

This article presents results for the last unknown two-loop contributions to the $Z$-boson partial widths and $Z$-peak cross-section. These are the so-called bosonic electroweak two-loop corrections, where "bosonic" refers to diagrams…

High Energy Physics - Phenomenology · Physics 2018-06-27 Ievgen Dubovyk , Ayres Freitas , Janusz Gluza , Tord Riemann , Johann Usovitsch