English
Related papers

Related papers: Two-loop electroweak corrections to the $\rho$ par…

200 papers

New heavy particles in an SU(2)_L multiplet, sometimes introduced in extensions of the standard model, have highly degenerate tree-level mass M if their couplings to the Higgs bosons are very small or forbidden. However, loop corrections…

High Energy Physics - Phenomenology · Physics 2009-12-22 Youichi Yamada

Effects of strong interactions on the two loop electroweak radiative corrections to the muon anomalous magnetic moment, $a_\mu=(g_\mu-2)/2$, are examined. Short-distance logs are shown to be unaffected. Computation of long-distance…

High Energy Physics - Phenomenology · Physics 2014-11-17 Andrzej Czarnecki , William J. Marciano , Arkady Vainshtein

Radiative corrections to both perturbative and non-perturbative contributions are added to existing calculations of the Isgur-Wise function $\xi_{IW}$. To this end, we develop a method for calculating two-loop integrals in the heavy quark…

High Energy Physics - Phenomenology · Physics 2010-11-01 E. Bagan , P. Ball , P. Gosdzinsky

We present the complete set of Feynman rules producing the rational terms of kind R_2 needed to perform any 1-loop calculation in the Electroweak Standard Model. Our results are given both in the 't Hooft-Veltman and in the Four Dimensional…

High Energy Physics - Phenomenology · Physics 2010-10-28 M. V. Garzelli , I. Malamos , R. Pittau

The vacuum polarization functions $\Pi(q^2)$ of charged and neutral gauge bosons which arise from top and bottom quark loops lead to important shifts in relations between electroweak parameters which can be measured with ever-increasing…

High Energy Physics - Phenomenology · Physics 2009-10-28 K. G. Chetyrkin , J. H. Kuehn , M. Steinhauser

Using the pinch technique we construct at one-loop order a neutrino charge radius, which is finite, depends neither on the gauge-fixing parameter nor on the gauge-fixing scheme employed, and is process-independent. This definition stems…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Bernabeu , L. G. Cabral-Rosetti , J. Papavassiliou , J. Vidal

We investigate the electroweak phase transition in the real-singlet extension of the Standard Model at two-loop level, building upon existing one-loop studies. We calculate the effective potential in the high-temperature approximation and…

High Energy Physics - Phenomenology · Physics 2024-03-05 Lauri Niemi , Philipp Schicho , Tuomas V. I. Tenkanen

We implement a one-loop analysis of the $\rho$ parameter in the Left Right Twin Higgs model, including the logarithmically enhanced contributions from both fermion and scalar loops. Numerical results show that the one-loop contributions are…

High Energy Physics - Phenomenology · Physics 2007-10-16 Dong-Won Jung , Jae Yong Lee

In processes at the energy much higher than electroweak scale, weak boson mass act as the infrared cutoff in weak boson loops and resulting Sudakov log corrections can be as large as 10%. Since electroweak theory is off-diagonally broken…

High Energy Physics - Phenomenology · Physics 2017-08-23 Hiroyuki Kawamura

Higher-order radiative corrections play an important role in precision studies of the electroweak and Higgs sector, as well as for the detailed understanding of large backgrounds to new physics searches. For corrections beyond the one-loop…

High Energy Physics - Phenomenology · Physics 2016-08-16 Ayres Freitas

We obtain the two-loop effective potential for general renormalizable theories, using a generalized gauge-fixing scheme that includes as special cases the background-field $R_\xi$ gauges, the Fermi gauges, and the familiar Landau gauge, and…

High Energy Physics - Phenomenology · Physics 2018-10-24 Stephen P. Martin , Hiren H. Patel

In this paper we study the calculation of multiloop Feynman integrals that cannot be expressed in terms of multiple polylogarithms. We show in detail how certain types of two- and three-point functions at two loops, which appear in the…

High Energy Physics - Phenomenology · Physics 2019-06-26 Johannes Broedel , Claude Duhr , Falko Dulat , Brenda Penante , Lorenzo Tancredi

We derive the high energy asymptotic of one- and two-loop corrections in the next-to-next-to-leading logarithmic approximation to the differential cross section of $W$-pair production at the LHC. For large invariant mass of the W-pair the…

High Energy Physics - Phenomenology · Physics 2015-03-17 J. H. Kuhn , F. Metzler , A. A. Penin , S. Uccirati

We review a recent calculation of the two-loop next-to-leading logarithmic electroweak corrections to the form factors for massless chiral fermions coupling to an SU(2)xU(1) singlet gauge boson.

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Pozzorini

We present a complete calculation of the next-to-next-to-leading (NNLO) electroweak corrections involving closed fermion loops to the $e^+ e^- \to ZH$ process. This has been achieved by using a semi-numerical technique for the two-loop…

High Energy Physics - Phenomenology · Physics 2023-02-01 Ayres Freitas , Qian Song

A reexamination is made of one-loop oblique electroweak corrections. General definitions are given of the oblique parameters without reference to any $q^2$-expansion scheme. The old oblique parameters S,T and U are defined as differences of…

High Energy Physics - Phenomenology · Physics 2014-11-17 Anirban Kundu , Probir Roy

This paper studies models with extended electroweak gauge sectors of the form SU(2) x SU(2) x U(1) x [SU(2) or U(1)]. We establish the general behavior of corrections to precision electroweak observables in this class of theories and…

High Energy Physics - Phenomenology · Physics 2016-09-06 R. S. Chivukula , H. -J. He , J. Howard , E. H. Simmons

Numerical calculation of two-loop electroweak corrections to the muon anomalous magnetic moment ($g$-2) is done based on, on shell renormalization scheme (OS) and free quark model (FQM). The GRACE-FORM system is used to generate Feynman…

High Energy Physics - Phenomenology · Physics 2019-04-17 Tadashi Ishikawa , Nobuya Nakazawa , Yoshiaki Yasui

We reemphasize the importance of discriminating fermion-loop and bosonic electroweak corrections in the analysis of electroweak precision data. Most recent data are indeed precise enough to require corrections beyond (trivial) fermion…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dieter Schildknecht

In a recent paper, we introduced a new Little Higgs model, which contains the gauge structure $SU(2)^3\times U(1)$, embedded in an approximate global $SO(5)\times SO(5)$ symmetry. After breaking to the standard model, $SU(2)_L \times…

High Energy Physics - Phenomenology · Physics 2013-05-30 Roshan Foadi , Carl R. Schmidt , Jiang-Hao Yu