English
Related papers

Related papers: Electroweak Corrections to the Top Quark Decay

200 papers

We present O(alpha_s^2) corrections to the decay t-->bW in the limit of a very large top quark mass, m_t >> m_W. We find that the O(alpha_s^2) effects decrease the top quark decay width Gamma_t by about 2%: Gamma_t =…

High Energy Physics - Phenomenology · Physics 2009-10-31 Andrzej Czarnecki , Kirill Melnikov

We calculate the electroweak-like one-loop supersymmetric contributions to the rare and flavor-violating decay of the top quark into a charm quark and a gauge boson: $t->c V$, with $V=\gamma,Z,g$. We consider loops of both charginos and…

High Energy Physics - Phenomenology · Physics 2009-10-30 Jorge L. Lopez , D. V. Nanopoulos , Raghavan Rangarajan

We present a new method for the determination of the Cabibbo-Kobayashi-Maskawa quark mixing matrix element $|V_{tb}|$ from electroweak loop corrections, in particular those affecting the process $Z\to b\bar{b}$. From a combined analysis of…

High Energy Physics - Phenomenology · Physics 2009-10-30 John Swain , Lucas Taylor

We report on the status of an ongoing calculation of the NLO electroweak corrections to sequential polarized top quark decays $t(\uparrow) \to X_b +W^+ (\to \ell^+ +\nu_\ell)$.

High Energy Physics - Phenomenology · Physics 2018-01-09 S. Groote , J. G. Körner

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

We review the one-loop corrections to the partial decay width of sbottom-quark into a top quark and a chargino for the parameter space relevant to the TESLA e+e- linear collider. We present the results available in the literature for the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jaume Guasch , Wolfgang Hollik , Joan Sola

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

Heavy squark decays into top and charginos or neutralinos could be an unexpected source of top quarks at hadron colliders. A detailed treatment of these processes is necessary for a reliable calculation of both the top quark production…

High Energy Physics - Phenomenology · Physics 2011-01-27 Jaume Guasch , Joan Sola , Wolfgang Hollik

We calculate the full electroweak one-loop corrections to the decay of the CP-odd Higgs boson A^0 into scalar quarks in the minimal supersymmetric extension of the Standard Model (MSSM). Due to the complex structure of the electroweak…

High Energy Physics - Phenomenology · Physics 2014-11-17 C. Weber , H. Eberl , W. Majerotto

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 electroweak corrections to the partial widths of the $H^+ \to \tilde{\chi}^+_i \tilde{\chi}_j^0 (i=1,j=1,2)$ decays including one-loop diagrams of the third generation quarks and squarks, are investigated within the Supersymmetric…

High Energy Physics - Phenomenology · Physics 2019-08-17 Wan Lang-Hui , Ma Wen-Gan , Zhang Ren-You , Jiang Yi

We discuss the QCD corrections to the large-$m_t$ electroweak contributions to $\Delta r$ and to the process $Z\to b \bar b$ as two of the most representative examples. This needs the construction of an effetive field theory below the top…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Peris

At energies much larger than the mass of the weak gauge bosons, electroweak radiative corrections can lead to significant corrections. At 1 TeV the one loop corrections can be of ${\cal O} (20 %)$ due to large contributions of the Sudakov…

High Energy Physics - Phenomenology · Physics 2009-10-31 Michael Melles

Recently exact results for the complete electroweak two-loop contributions to the effective weak mixing angle were published. This paper illustrates the techniques used for this computation, in particular the methods for evaluating the loop…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Awramik , M. Czakon , A. Freitas

The four-loop QCD corrections to the electroweak $\rho$-parameter arising from top and bottom quark loops are computed. Specifically we evaluate the missing ``non-singlet'' piece. Using algebraic methods the amplitude is reduced to a set of…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. G. Chetyrkin , M. Faisst , J. H. Kühn , P. Maierhoefer , C. Sturm

We compute the leading-log QED, the next-to-leading-log QED-QCD, and the electroweak corrections to the charm quark contribution relevant for the rare decay K+ -> pi+ nu nu-bar. The corresponding parameter P_c(X) is increased by up to 2%…

High Energy Physics - Phenomenology · Physics 2008-11-26 Joachim Brod , Martin Gorbahn

We investigate the one-loop supersymmetric QCD (SUSY-QCD) and electroweak (SUSY-EW) corrections to the top quark decay into a b-quark and a longitudinal or transverse W-boson. The corrections are presented in terms of the longitudinal ratio…

High Energy Physics - Phenomenology · Physics 2011-03-23 Junjie Cao , Robert J. Oakes , Fei Wang , Jin Min Yang

We study the impact of the full ${\cal O}(\alpha_{s})$ QCD and ${\cal O}(\alpha_{ew})$ electroweak (EW) radiative corrections to the $e^+e^- \to t \bar t Z^0$ process in the standard model (SM), and investigate the dependence of the…

High Energy Physics - Phenomenology · Physics 2014-11-18 Dai Lei , Ma Wen-Gan , Zhang Ren-You , Guo Lei , Wang Shao-Ming

A combination of algebraical and numerical techniques for calculating two-loop top-quark and Higgs-boson corrections to electroweak precision observables like $\Delta r$ or the $\rho$-parameter is presented. The renormalization is performed…

High Energy Physics - Phenomenology · Physics 2011-03-02 S. Bauberger , 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