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Related papers: Electroweak Precision Observables within a Fourth …

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We calculate a number of observables related to particle-antiparticle mixing and the branching ratios for the most interesting rare and CP-violating K and B decays in the Standard Model (SM3) extended by a fourth generation of quarks and…

High Energy Physics - Phenomenology · Physics 2010-12-01 Andrzej J. Buras , Björn Duling , Thorsten Feldmann , Tillmann Heidsieck , Christoph Promberger , Stefan Recksiegel

The complete O(alpha) electroweak radiative corrections to e+e- --> WW --> 4f in the electroweak Standard Model are presented in the double-pole approximation. We give analytical and numerical results for the non-factorizable corrections…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Roth

In this paper, we present the one-loop radiative corrections to the electroweak precision observable $\Delta \rho$ coming from the $I_W=1$ multiplet excited leptons. We have calculated the couplings of the exotic lepton triplet to the…

High Energy Physics - Phenomenology · Physics 2021-05-19 M. Rehman , M. E. Gomez , O. Panella

Electroweak Precision Measurements are stringent tests of the Standard Model and sensitive probes to New Physics. Accurate studies of the $Z$-boson couplings to the first-generation quarks, which are currently constrained from LEP data to a…

High Energy Physics - Phenomenology · Physics 2025-11-13 Krzysztof Mękała , Daniel Jeans , Jürgen Reuter , Junping Tian , Aleksander Filip Żarnecki

In the Standard Model Effective Field Theory (SMEFT), operators involving the top quark are generally difficult to probe, and can generate sizable loop contributions to the electroweak precision observables, measured by past and future…

High Energy Physics - Phenomenology · Physics 2022-11-09 Yiming Liu , Yuhao Wang , Cen Zhang , Lei Zhang , Jiayin Gu

The leading corrections to electroweak precision observables in the MSSM with non-minimal flavor violation (NMFV) are calculated and the effects on M_W and sin^2 theta_eff are analyzed. The corrections are obtained by evaluating the full…

High Energy Physics - Phenomenology · Physics 2011-01-27 S. Heinemeyer , W. Hollik , F. Merz , S. Penaranda

Flavor physics, like cosmology, is likely in need of new basic ideas; the puzzles of elementary particle mass hierarchies and in particular the e-mu-tau and neutrino ones still remain mysteries. In this paper a new idea of dynamical…

General Physics · Physics 2009-04-06 E. M. Lipmanov

We show how precision electroweak data, assuming CP conservation and flavor universality, despite being sensitive to 20 dimension 6 operators, constrain severely only 9 combinations of them. We define a set of 7 oblique parameters $\hat S,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Guido Marandella

We employ a bottom-up and model-independent technique to search for non-Abelian discrete flavour symmetries capable of predicting viable CKM and PMNS matrices alongside of special patterns of leptoquark couplings. In particular, we analyze…

High Energy Physics - Phenomenology · Physics 2020-02-19 Jordan Bernigaud , Ivo de Medeiros Varzielas , Jim Talbert

We discuss whether quark, charged lepton and neutrino masses and mixing angles may be related by an extended flavour and family symmetry group. We show that current measurements of all fermion masses and mixing angles are consistent with a…

High Energy Physics - Phenomenology · Physics 2010-04-05 G. G. Ross , L. Velasco-Sevilla

We calculate the complete O(alpha) electroweak radiative corrections to e+e- --> WW --> 4f in the electroweak Standard Model in the double-pole approximation. We give analytical results for the non-factorizable virtual corrections and…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , S. Dittmaier , M. Roth , D. Wackeroth

We present a simple method for analyzing the impact of precision electroweak data above and below the Z-peak on flavour-conserving heavy new physics. We find that experiments have probed about ten combinations of new physics effects, which…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Cacciapaglia , C. Csáki , G. Marandella , A. Strumia

We investigated the electroweak corrections from one-loop diagrams involving the third generation (s)quarks to the decay width of process $\tilde{\chi}_1^+ \to W^+ \tilde{\chi}_1^{0}$ in the framework of the Minimal Supersymmetric Standard…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zhang Ren-You , Ma Wen-Gan , Wan Lang-Hui

We establish constraints on a general four-fermion contact interaction from precise measurements of electroweak parameters. We compute the one-loop contribution for the leptonic $Z$ width, anomalous magnetic, weak-magnetic, electric and…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. C. Gonzalez-Garcia , A. Gusso , S. F. Novaes

Flavour- and CP-violating electromagnetic or chromomagnetic dipole operators in the quark sector are generated in a large class of new physics models and are strongly constrained by measurements of the neutron electric dipole moment and…

High Energy Physics - Phenomenology · Physics 2015-12-21 Matthias König , Matthias Neubert , David M. Straub

We present the calculation of next-to-leading-order electroweak corrections to W-boson pair production at the LHC, taking off-shell effects of the W bosons and their leptonic decays into account in the framework of the so-called double-pole…

High Energy Physics - Phenomenology · Physics 2015-06-17 M. Billoni , S. Dittmaier , B. Jager , C. Speckner

We have considered a general 5D warped model with SM fields propagating in the bulk and computed explicit expressions for oblique and non-oblique electroweak observables as well as for flavor and CP violating effective four-fermion…

High Energy Physics - Phenomenology · Physics 2015-05-30 Joan A. Cabrer , Gero von Gersdorff , Mariano Quiros

Complete electroweak two-loop corrections to the process $gg \to H$ are presented and discussed in a Standard Model with a fourth generation of heavy fermions. The latter is studied at the LHC to put exclusion limits on a fourth generation…

High Energy Physics - Phenomenology · Physics 2015-05-30 Giampiero Passarino , Christian Sturm , Sandro Uccirati

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

Next-to-Leading-Order (NLO) effects play a crucial role in tests of the Standard Model (SM), and require careful theoretical evaluation. Electroweak physics, which has just entered the precision age, is an excellent place to search for new…

Nuclear Theory · Physics 2010-02-11 A. Aleksejevs , S. Barkanova