English
Related papers

Related papers: Two-loop electroweak fermionic corrections to sin^…

200 papers

Multi-loop integrals can be evaluated numerically using Mellin-Barnes representations. Here this technique is applied to the calculation of electroweak two-loop correction with closed fermion loops for two observables: the effective weak…

High Energy Physics - Phenomenology · Physics 2013-10-14 A. Freitas , Yi-Cheng Huang

The complete two-loop electroweak fermionic corrections to the effective leptonic weak mixing angle, sin^2(theta_eff), are now available. Here we shortly present the methods applied and illustrate the implications on indirect prediction for…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Awramik , M. Czakon , A. Freitas , G. Weiglein

We present a complete calculation of the contributions to the effective leptonic weak mixing angle, sin^2theta_eff, generated by closed fermion loops at the two-loop level of the electroweak interactions. This quantity is the source of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Awramik , M. Czakon , A. Freitas , G. Weiglein

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

We present the results from a calculation of the full electroweak two-loop fermionic contributions to the effective leptonic mixing angle of the $Z$ boson, $\sin^2\theta_{eff}$, in the Standard Model. On-shell renormalization and analytic…

High Energy Physics - Phenomenology · Physics 2009-11-11 W. Hollik , U. Meier , S. Uccirati

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 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

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

We present Standard Model predictions for the complete set of phenomenologically relevant electroweak precision pseudo-observables related to the Z-boson: the leptonic and bottom-quark effective weak mixing angles $\sin^2\theta_{\rm…

High Energy Physics - Phenomenology · Physics 2020-01-13 Ievgen Dubovyk , Ayres Freitas , Janusz Gluza , Tord Riemann , Johann Usovitsch

We derive logarithmically enhanced two-loop virtual electroweak corrections for arbitrary fermion-scattering processes at the TeV scale. This extends results previously obtained for massless fermion scattering to processes that involve also…

High Energy Physics - Phenomenology · Physics 2009-11-19 Ansgar Denner , Bernd Jantzen , Stefano Pozzorini

The one-loop corrections to the weak mixing angle $\sin^2\theta_{eff}^b$ derived from the $Z{\bar b}b$ vertex, are known since 1985. It took another 30 years to calculate the complete electroweak two-loop corrections to…

High Energy Physics - Phenomenology · Physics 2016-11-08 I. Dubovyk , A. Freitas , J. Gluza , T. Riemann , J. Usovitsch

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

We discuss two-loop leading and angular-dependent next-to-leading logarithmic electroweak virtual corrections to arbitrary processes at energies above the electroweak scale. The relevant Feynman diagrams involving soft-collinear gauge…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ansgar Denner , Michael Melles , Stefano Pozzorini

Low- and intermediate mass Higgs bosons decay preferably into fermion pairs. The one-loop electroweak corrections to the respective decay rates are dominated by a flavour-independent term of ${\cal O}(G_Fm_t^2)$. We calculate the two-loop…

High Energy Physics - Phenomenology · Physics 2009-10-28 Bernd A. Kniehl

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

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 heavy-top two-loop corrections to the \Zbb~vertex are determined from a direct evaluation of the corresponding Feynman diagrams in the large \Mt~limit. %The calculation is done in the naive %dimensional regularization scheme…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. Denner , W. Hollik , B. Lampe

We present the complete bosonic contributions to the effective weak mixing angle, $\seff$, at the two-loop level in the electroweak interactions. We find their size to be about three times smaller than inferred from simple estimates from…

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

We provide a compendium of techniques that can be used to compute $O(N_f\alpha^2)$ corrections to low-energy electroweak processes. Specifically, these are the 2-loop electroweak corrections containing a light fermion loop. It is shown that…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Akhoury , Paresh Malde , Robin G. Stuart

We give some details of the recently completed calculation of the full two-loop fermionic corrections to the effective leptonic weak mixing angle. Among others, we describe the C++ library DiaGen/IdSolver, which was used to reduce the…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. Awramik , M. Czakon , A. Freitas , G. Weiglein
‹ Prev 1 2 3 10 Next ›