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Related papers: Two-Loop Electroweak Corrections for the K -> pi n…

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We summarize a recent strategy for a global analysis of the B -> pi pi, pi K systems and rare decays. We find that the present B -> pi pi and B -> pi K data cannot be simultaneously described in the Standard Model. In a simple extension in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras , Robert Fleischer , Stefan Recksiegel , Felix Schwab

Two loop electroweak corrections to b --> s gamma decays are computed. Fermion and photonic loop effects are found to reduce R = BR(b --> s gamma)/BR(b --> c e nu) by 8+-2% and lead to the standard model prediction BR(B --> X_s gamma)=(3.28…

High Energy Physics - Phenomenology · Physics 2009-10-31 Andrzej Czarnecki , William J. Marciano

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

Recently exact results for the complete fermionic two-loop contributions to the prediction for the W-boson mass from muon decay in the electroweak Standard Model have been published [hep-ph/0007091]. This paper illustrates the techniques…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Freitas , W. Hollik , W. Walter , G. 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

We have calculated the one-loop electroweak corrections to the decay t-> bW+, including the counterterm for the CKM matrix elements V(tb). Previous calculations used an incorrect delta V(tb) that led to a gauge dependent amplitude. However,…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. M. Oliveira , L. Bruecher , R. Santos , A. Barroso

We present the calculation of the electroweak corrections for squark-antisquark pair production at the LHC within the Minimal Supersymmetric Standard Model. Taking into account all possible chirality and light-flavor configurations, we…

High Energy Physics - Phenomenology · Physics 2015-10-15 Wolfgang Hollik , Jonas M. Lindert , Edoardo Mirabella , Davide Pagani

The Standard-Model interpretation of the ratios of charged and neutral B-> pi K rates, R_c and R_n, respectively, points towards a puzzling picture. Since these observables are affected significantly by colour-allowed electroweak (EW)…

High Energy Physics - Phenomenology · Physics 2016-09-06 Andrzej J. Buras , Robert Fleischer , Stefan Recksiegel , Felix Schwab

We propose a method to quantify the Standard Model uncertainty in B to K pi decays using the experimental data, assuming that power counting provides a reasonable estimate of the subleading terms in the 1/mb expansion. Using this method, we…

High Energy Physics - Phenomenology · Physics 2009-04-06 M. Ciuchini , E. Franco , G. Martinelli , M. Pierini , L. Silvestrini

We analyse subleading electroweak effects in the top anti-top resonance production region in e+ e- collisions which arise due to the decay of the top and anti-top quarks into the W+ W- b bbar final state. These are NLO corrections adopting…

High Energy Physics - Phenomenology · Physics 2010-08-24 M. Beneke , B. Jantzen , P. Ruiz-Femenia

We analyze the branching ratio for the FCNC mode $K^+\to\pi^+\nu\bar\nu$\ in the standard model with QCD effects taken into account consistently to next-to-leading order. This involves a two-loop renormalization group analysis for the charm…

High Energy Physics - Phenomenology · Physics 2009-10-09 G. Buchalla , A. J. Buras

Recently, the ATLAS and CMS collaborations jointly announced the first evidence of the rare Higgs boson decay channel $H\to Z\gamma$, with a ratio of $2.2\pm 0.7$ times the leading order standard model (SM) prediction. In order to face this…

High Energy Physics - Phenomenology · Physics 2024-09-04 Zi-Qiang Chen , Long-Bin Chen , Cong-Feng Qiao , Ruilin Zhu

Recent results from the first phase of the E787 experiment and an update on the current status are presented. From the first phase the limit on the K+ -> pi+ nu nu (pnn) branching ratio is BR(pnn) < 2.4e-9 (90%CL). An observation of the…

High Energy Physics - Experiment · Physics 2007-05-23 Steve Kettell

A review is given on the quantum correction $\Delta r$ in the $W$--$Z$ mass correlation at the electroweak two-loop level, as derived from the calculation of the muon lifetime in the Standard Model. Exact results for $\Delta r$ and the…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Freitas , S. Heinemeyer , W. Hollik , W. Walter , G. Weiglein

The complete electroweak O(alpha) corrections have been calculated for the charged-current four-fermion production processes e+e- --> nu_tau tau+ mu- anti-nu_mu, u anti-d mu- anti-nu_mu, and u anti-d s anti-c. Here, technical details of…

High Energy Physics - Phenomenology · Physics 2011-08-30 A. Denner , S. Dittmaier , M. Roth , L. H. Wieders

We present a concise review of the recent theoretical progress concerning the standard model calculations of the rare K_L -> pi^0 nu anti-nu, K^+ -> pi^+ nu anti-nu (gamma), anti-B -> X_s gamma, and anti-B -> X_s l^+ l^- decays. The current…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ulrich Haisch

We calculate the one-loop electroweak corrections to e+e- to WWZ and e+e- to ZZZ and analyse their impacts on both the total cross section and some key distributions. These processes are important for the measurements of the quartic…

High Energy Physics - Phenomenology · Physics 2010-04-27 Fawzi Boudjema , Le Duc Ninh , Sun Hao , Marcus M. Weber

We summarize the theoretical virtues of the rare K -> pi nu nu-bar decays and emphasize the unique role of KL -> pi0 nu nu-bar in probing the nature of physics beyond the Standard Model, in particular concerning possible new sources of CP…

High Energy Physics - Phenomenology · Physics 2014-11-18 Douglas Bryman , Andrzej J. Buras , Gino Isidori , Laurence Littenberg

We calculate the typical size of loop corrections to electroweak observables arising from non-standard $Z {\overline t } t$ and $W t b$ vertices. We use an effective Lagrangian formalism based on the electroweak gauge group $SU(2)_L\times…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Dawson , G. Valencia

We have examined the evidence for the electroweak radiative corrections in the LEP precision data along with the intriguing possibility that the QED corrections only may be sufficient to fit the data. We find that the situation is very…

High Energy Physics - Phenomenology · Physics 2009-09-25 Kyungsik Kang , Sin Kyu Kang