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Related papers: Order $N_f\alpha^2$ Corrections in Low-Energy Elec…

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The dominant electroweak corrections to the production cross sections and partial decay widths of a light Standard-Model Higgs boson, with mass M_H << 2m_t, are due to top-quark loops. By means of a low-energy theorem, we study at the…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. Djouadi , P. Gambino , B. A. Kniehl

We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew} m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the process $H^+\to W^+h$ in the Minimal Supersymmetric Model. These corrections arise from the virtual…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ya Sheng Yang , Chong Sheng Li

We have completed the calculation of pure-recoil corrections of order $(Z \alpha)^6$ to Coulombic bound states of two spin-1/2 fermions without approximation in the particle masses. Our result applies to systems of arbitrary mass ratio such…

High Energy Physics - Phenomenology · Physics 2023-01-25 Gregory S. Adkins , Jonathan Gomprecht , Yanxi Li , Evan Shinn

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 two-loop corrections in primordial power spectrum in models of single field inflation incorporating an intermediate USR phase employed for PBHs formation. Among the total eleven one-particle irreducible Feynman diagrams, we…

High Energy Physics - Phenomenology · Physics 2024-12-16 Hassan Firouzjahi

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

We present results for the corrections of order alpha^2 (Z alpha)^5 to the Lamb shift. We compute all the contributing Feynman diagrams in dimensional regularization and a general covariant gauge using a mixture of analytical and numerical…

High Energy Physics - Phenomenology · Physics 2014-11-20 Matthew Dowling , Jorge Mondejar , Jan H. Piclum , Andrzej Czarnecki

We present results for the O(alpha_s) virtual corrections to q g -> W b bbar q' obtained with a new automatized approach to the evaluation of one-loop amplitudes in terms of Feynman diagrams. Together with the O(alpha_s) corrections to q q'…

High Energy Physics - Phenomenology · Physics 2015-05-30 Laura Reina , Thomas Schutzmeier

We present results for the corrections of order alpha^2 (Z alpha) E_F to the hyperfine splitting of muonium. We compute all the contributing Feynman diagrams in dimensional regularization and a general covariant gauge using a mixture of…

High Energy Physics - Phenomenology · Physics 2015-03-17 Jorge Mondejar , Jan H. Piclum , Andrzej Czarnecki

Some of the most interesting Higgs-production processes at future e+ e- colliders are of the type e+ e- -> f anti-f H. We present a calculation of the complete O(alpha) corrections to these processes in the Standard Model for final-state…

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

We present precise predictions for the processes e+ e- -> WW -> 4f(gamma) at LEP2 and future Linear-Collider (LC) energies obtained with the Monte Carlo generator RacoonWW. The program RacoonWW includes the complete O(alpha) electroweak…

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

We compute the eighth-order fermionic corrections involving two and three closed massless fermion loops to the anomalous magnetic moment of the muon. The required four-loop on-shell integrals are classified and explicit analytical results…

High Energy Physics - Phenomenology · Physics 2015-06-12 Roman Lee , Peter Marquard , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We consider the impact of O(alpha^2) hadronic corrections to the energy spectrum of the decay electron in muon decay. We find that the correction can be described, within good approximation, by a linear function in the electron energy.…

High Energy Physics - Phenomenology · Physics 2009-01-07 A. I. Davydychev , K. Schilcher , H. Spiesberger

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 compute the virtual O(\alpha_s^3 n_f^2) corrections to the heavy quark vector current correlator in terms of expansions in the external momentum and as an exact numerical solution. As a byproduct, the available high-energy expansion at…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Czakon , T. Schutzmeier

We have calculated the complete electroweak O(alpha) radiative corrections to the single Higgs-boson production processes e+ e- --> nu_l anti-nu_l H (l=e,mu,tau) in the electroweak Standard Model. Initial-state radiation beyond O(alpha) is…

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

The cross-section for $\gamma\gamma\to t \bar t$ with arbitrary polarized photons is calculated within the electroweak Standard Model including the complete virtual and soft-photonic $O(\alpha)$ corrections. We present a detailed numerical…

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

Some methods for the numerical computation of two-loop non-infrared vertices are reviewed. A new method is also proposed and compared to the old ones. Finally, some preliminary results are presented, concerning the evaluation of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sandro Uccirati

We study the leading log infrared behavior of electroweak corrections at TeV scale energies, that will be reached by next generation of linear colliders (NLC). We show that, contrary to what happens at typical LEP energies, it is not…

High Energy Physics - Phenomenology · Physics 2009-10-31 P. Ciafaloni , D. Comelli

A new framework to study electroweak physics at one-loop level in general ${\rm SU(2)_L \times U(1)_Y}$ theories is introduced. It separates the 1-loop corrections into two pieces: process specific ones from vertex and box contributions and…

High Energy Physics - Phenomenology · Physics 2008-02-03 K. Hagiwara , S. Matsumoto , C. S. Kim