English
Related papers

Related papers: Two-loop Vertices with Vacuum Polarization Inserti…

200 papers

In this paper we present the complete two-loop vertex corrections to scalar and pseudo-scalar Higgs boson production for general colour factors for the gauge group ${\rm SU(N)}$ in the limit where the top quark mass gets infinite. We derive…

High Energy Physics - Phenomenology · Physics 2010-04-05 V. Ravindran , J. Smith , W. L. van Neerven

We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…

High Energy Physics - Phenomenology · Physics 2009-07-29 J. Gluza , A. Mitov , S. Moch , T. Riemann

We discuss a mapping of lattice QED with two flavors and a chemical potential to dual variables, which are surfaces for the gauge fields and loops for the fermions. The gauge fields are completely dualized and the corresponding dual…

High Energy Physics - Lattice · Physics 2015-02-10 Michael Kniely , Christof Gattringer

The two-loop massive operator matrix elements for the fermionic local twist--2 operators with external massive fermion lines in Quantum Electrodynamics (QED) are calculated up to the constant terms in the dimensional parameter $\epsilon = D…

High Energy Physics - Phenomenology · Physics 2011-11-02 Johannes Blümlein , Abilio De Freitas , Wilhelmus van Neerven

We consider two-loop leading and next-to-leading logarithmic virtual corrections to arbitrary processes with external massless fermions in the electroweak Standard Model at energies well above the electroweak scale. Using the…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , B. Jantzen , S. Pozzorini

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

We describe the calculation of the two--loop massive operator matrix elements for massive external fermions. These matrix elements are needed for the calculation of the $O(\alpha^2)$ initial state radiative corrections to $e^+e^-$…

High Energy Physics - Phenomenology · Physics 2009-04-14 J. Blümlein , A. De Freitas , W. van Neerven

We describe an efficient scheme for evaluating higher order contributions to primordial cosmological perturbations using the "in-in" formalism, which is the basis of modern calculations of non-Gaussian and higher order contributions to the…

High Energy Physics - Theory · Physics 2009-11-05 Peter Adshead , Richard Easther , Eugene A. Lim

We calculate the non-forward quark matrix elements for operators with two covariant derivatives in one-loop lattice perturbation theory using Wilson fermions. These matrix elements are needed in the renormalisation of the second moment of…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , H. Perlt , P. E. L. Rakow , A. Schäfer , G. Schierholz , A. Schiller

A complete, gauge-invariant computation of two loop virtual corrections involving closed fermion loops to the polarized M{\o}ller scattering asymmetry is presented. The set of contributions involving two closed fermion loops and the set…

High Energy Physics - Phenomenology · Physics 2021-04-07 Yong Du , Ayres Freitas , Hiren H. Patel , Michael J. Ramsey-Musolf

Motivated by the precision results in the electroweak theory studies of two-loopFeynman diagrams are performed. Specifically this paper gives a contribution to the knowledge of massive two-loop self-energy diagrams in arbitrary and…

High Energy Physics - Phenomenology · Physics 2011-09-30 S. Bauberger , F. A. Berends , M. Boehm , M. Buza

In the heavy quark effective theory, hadronic matrix elements of currents between two hadrons containing a heavy quark are expanded in inverse powers of the heavy quark masses, with coefficients that are functions of the kinematic variable…

High Energy Physics - Phenomenology · Physics 2009-10-22 Adam F. Falk , Matthias Neubert

The shape function describes (non-perturbative) Fermi motion effects in semi-inclusive heavy flavour decay. Its renormalization properties are substantially dependent on the kind of ultraviolet regulator used. For example, the double…

High Energy Physics - Phenomenology · Physics 2009-10-31 U. Aglietti

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 present the two-loop corrected operator matrix elements calculated in N-dimensional regularization up to the finite terms which survive in the limit $\epsilon = N - 4 \to 0 $. The anomalous dimensions of the local operators have been…

High Energy Physics - Phenomenology · Physics 2009-10-31 Y. Matiounine , J. Smith , W. L. van Neerven

We consider a process of quasielastic $e\mu$ large-angle scattering at high energies with radiative corrections up to a two-loop level. A lowest order radiative correction arising both from one-loop virtual photon emission and a real soft…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. V. Bytev , E. A. Kuraev , B. G. Shaikhatdenov

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

Using the approach based on conformal symmetry we calculate the two-loop coefficient function for the vector flavor-nonsinglet contribution to deeply-virtual Compton scattering (DVCS). The analytic expression for the coefficient function in…

High Energy Physics - Phenomenology · Physics 2021-08-03 V. M. Braun , A. N. Manashov , S. Moch , J. Schoenleber

Evaluation of three- and four-point diagrams with massless internal particles and arbitrary external momenta is considered. Exact results for some two-loop diagrams (planar and non-planar three-point contributions and the "double box"…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. I. Ussyukina , A. I. Davydychev

Using the parallel/orthogonal space method, we calculate the planar two-loop three-point diagram and two rotated reduced planar two-loop three-point diagrams. Together with the crossed topology, these diagrams are the most complicated ones…

High Energy Physics - Phenomenology · Physics 2009-01-07 Stefan Groote , Markus M. Knodel