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Related papers: Two-Loop Electroweak Corrections to $\Delta r$

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The prediction of the effective electroweak mixing angle $\sin^2\theta_{\rm eff}^{\rm b}$ in the Standard Model at two-loop accuracy has now been completed by the first calculation of the bosonic two-loop corrections to the $Z{\bar b}b$…

High Energy Physics - Phenomenology · Physics 2016-10-04 Ievgen Dubovyk , Ayres Freitas , Janusz Gluza , Tord Riemann , Johann Usovitsch

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

The complete set of two-loop electroweak corrections to the decay width of the Higgs boson into two photons is presented. Two-loop contributions involving weak bosons and the top quark are computed in terms of an expansion in the Higgs…

High Energy Physics - Phenomenology · Physics 2010-04-05 Giuseppe Degrassi , Fabio Maltoni

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

The computation of the correction \Delta r in the W-Z mass correlation, derived from muon decay, is described at the two-loop level in the Standard Model. Technical aspects which become relevant at this level are studied, e.g.…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Freitas , S. Heinemeyer , W. Hollik , W. Walter , G. Weiglein

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 present a detailed evaluation of the bosonic two-loop electroweak corrections to the muon's anomalous magnetic moment. We study the Higgs mass dependence and find agreement with a previous evaluation in the large Higgs mass limit. We…

High Energy Physics - Phenomenology · Physics 2009-11-11 T. Gribouk , A. Czarnecki

We present complete one-loop radiative corrections to the decay rate of a top quark into a charged Higgs boson and a bottom quark, and for the decay of a charged Higgs boson into leptons. The results are discussed in the framework of the…

High Energy Physics - Phenomenology · Physics 2009-10-22 Andrzej Czarnecki

The two-loop QCD corrections to the $\rho$ parameter are derived in the Minimal Supersymmetric Standard Model. They turn out to be sizable and modify the one-loop result by up to 30%. Furthermore exact results for the gluonic corrections to…

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

Two-loop electroweak corrections to the muon anomalous magnetic moment are automatically calculated by using GRACE-FORM system, as a trial to extend our system for two-loop calculation. We adopt the non-linear gauge (NLG) to check the…

High Energy Physics - Phenomenology · Physics 2018-10-31 Tadashi Ishikawa , Nobuya Nakazawa , Yoshiaki Yasui

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

We discuss a recent analysis of a dominant two-loop electroweak correction, of O(G_F M_t^2), to the partial width of the decay of an intermediate-mass Higgs boson into a pair of photons. The asymptotic-expansion technique was used in order…

High Energy Physics - Phenomenology · Physics 2007-05-23 Bernd A. Kniehl

We study the relationships between the basic parameters of the on-shell renormalization scheme and their counterparts in the $\overline{\mathrm{MS}}$ scheme at full order ${\cal O}(\alpha^2)$ in the Standard Model. These enter as threshold…

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

The increasing accuracy of current and planned experiments to measure the anomalous magnetic moment of the muon requires more precision and reliability of its theoretical calculation. For this purpose, we calculate the differential cross…

High Energy Physics - Phenomenology · Physics 2023-08-21 V. S. Fadin , R. N. Lee

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

We have computed the two-loop, electroweak corrections to the production of a light and a heavy neutral, scalar Higgs-boson through the important gluon fusion process in the Two-Higgs-Doublet Model. We provide our results in various…

High Energy Physics - Phenomenology · Physics 2018-09-13 Laura Jenniches , Christian Sturm , Sandro Uccirati

We compute the dominant two-loop electroweak correction, of O(G_F M_t^2), to the partial width of the decay of an intermediate-mass Higgs boson into a pair of photons. We use the asymptotic-expansion technique in order to extract the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Frank Fugel , Bernd A. Kniehl , Matthias Steinhauser

We compute analytically the complete electroweak two-loop corrections to the $B^0-{\bar B}^0$ mixing. These corrections fix the normalization of the electroweak coupling employed in the extraction of $|V_{td}|$ and reduce the theoretical…

High Energy Physics - Phenomenology · Physics 2009-10-31 P. Gambino , A. Kwiatkowski , N. Pott

We calculate the full two-loop electroweak matching corrections to the operator governing the decay B_q --> l^+ l^- in the Standard Model. Their inclusion removes an electroweak scheme and scale uncertainty of about 7% of the branching…

High Energy Physics - Phenomenology · Physics 2014-02-26 Christoph Bobeth , Martin Gorbahn , Emmanuel Stamou

Of the the three best-measured electroweak observables, $\alpha$, $G_\mu$ and $M_Z$, the first two are extracted from low-energy processes. Both $G_\mu$ and $M_Z$ are now known to an accuracy of about 2 parts in $10^5$ and there is a…

High Energy Physics - Phenomenology · Physics 2007-05-23 Robin G. Stuart