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Related papers: Effective field theory for top physics

200 papers

We show that the anomalously large top quark forward-backward asymmetry observed by CDF and D\O\, can naturally be accommodated in models with flavor-violating couplings of a new massive spin-2 state to quarks. Regardless of its origin, the…

High Energy Physics - Phenomenology · Physics 2012-08-28 Benjamín Grinstein , Christopher W. Murphy , David Pirtskhalava , Patipan Uttayarat

Conformal totally symmetric arbitrary spin fermionic fields propagating in the flat space-time of even dimension greater than or equal to four are investigated. First-derivative metric-like formulation involving Fang-Fronsdal kinetic…

High Energy Physics - Theory · Physics 2021-05-18 R. R. Metsaev

Recent experiments of photon-nucleon and meson-nucleon scatterings have accumulated a lot of data for various meson production processes. One of the purposes of those experiments is to search for the missing resonances which are not…

High Energy Physics - Phenomenology · Physics 2024-12-30 Sang-Ho Kim , Yongseok Oh , Sangyeong Son , S. Sakinah , Myung-Ki Cheoun

A 2D- fractional supersymmetry theory is algebraically constructed. The Lagrangian is derived using an adapted superspace including, in addition to a scalar field, two fields with spins 1/3,2/3. This theory turns out to be a rational…

High Energy Physics - Theory · Physics 2008-11-26 A. Perez , M. Rausch de Traubenberg , P. Simon

We consider massive half-integer higher spin fields coupled to an external constant electromagnetic field in flat space of an arbitrary dimension and construct a gauge invariant Lagrangian in the linear approximation in the external field.…

High Energy Physics - Theory · Physics 2015-05-05 I. L. Buchbinder , V. A. Krykhtin , M. Tsulaia

We propose a new, chiral description for massive higher-spin particles in four spacetime dimensions, which facilitates the introduction of consistent interactions. As proof of concept, we formulate three theories, in which higher-spin…

High Energy Physics - Theory · Physics 2022-12-14 Alexander Ochirov , Evgeny Skvortsov

The top quark forward-backward asymmetry A_{FB}^t measured at the Tevatron is above the Standard Model prediction by more than 2-sigma deviation, which might be a harbinger for new physics. In this work we examine the contribution to…

High Energy Physics - Phenomenology · Physics 2010-04-06 Junjie Cao , Zhaoxia Heng , Lei Wu , Jin Min Yang

We propose a parametrization of anomalous Higgs-boson couplings that is both systematic and practical. It is based on the electroweak chiral Lagrangian, including a light Higgs boson, as the effective field theory (EFT) at the electroweak…

High Energy Physics - Phenomenology · Physics 2015-09-30 G. Buchalla , O. Cata , A. Celis , C. Krause

Motivated by past and recent analyses we critically re-examine the use of effective lagrangians in the literature to constrain new physics and to determine the `physics reach' of future experiments. We demonstrate that many calculations,…

High Energy Physics - Phenomenology · Physics 2010-11-01 C. P. Burgess , David London

A gauge-symmetric approach to effective Lagrangians is described with special emphasis on derivations of effective low-energy Lagrangians from QCD. The examples we discuss are based on exact rewritings of cut-off QCD in terms of new…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. H. Damgaard , H. B. Nielsen , R. Sollacher

The commonly used types of effective theory for vector mesons are reviewed and their relationships clarified. They are shown to correspond to different choices of field for spin-1 particles and the rules for transforming between them are…

High Energy Physics - Phenomenology · Physics 2011-07-19 Michael C. Birse

We describe low energy physics in the CFL and LOFF phases by means of effective lagrangians. In the CFL case we present also how to derive expressions for the parameters appearing in the lagrangian via weak coupling calculations taking…

High Energy Physics - Theory · Physics 2009-11-07 Roberto Casalbuoni

We review the recently developed general gauge invariant approach to Lagrangian construction for massive higher spin fields in Minkowski and AdS spaces of arbitrary dimension. Higher spin Lagrangian, describing the dynamics of the fields…

High Energy Physics - Theory · Physics 2007-12-11 I. L. Buchbinder , V. A. Krykhtin

An Effective Lagrangian description is useful for describing potential physics beyond the Standard Model. The method is illustrated by reference to interactions among the electroweak bosons ($W^\pm$ \& $Z^0$). The resulting estimates of the…

High Energy Physics - Phenomenology · Physics 2008-02-03 Martin B. Einhorn

Effective Lagrangians with dimension-six operators are widely used to analyse Higgs and other electroweak data. We show how to build a basis of operators such that each operator corresponds to a coupling which is well measured or will be in…

High Energy Physics - Phenomenology · Physics 2015-06-22 Eduard Masso

We give a complete set of 19 independent effective dimension 5 interactions involving the top and bottom quarks with the electroweak gauge bosons within the context of the chiral Lagrangian. The anomalous operators contribute to the leading…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. Larios , C. -P. Yuan

Forward-backward asymmetry $A_{\rm FB}$ is an essential observable to study the nature of coupling in the standard model and physics beyond the standard model, as shown at LEP and Tevatron. As a proton-proton collider, the LHC does not have…

High Energy Physics - Phenomenology · Physics 2011-02-01 You-kai Wang , Bo Xiao , Shou-hua Zhu

Fermion mixing is conveniently described using the effective Lagrangian formalism. We apply this approach to study top mixing in models with an infinite tower of Kaluza-Klein fermion excitations. In the Randall-Sundrum background with a…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. del Aguila , J. Santiago

A study on effective anomalous interactions up to dimension 5 of the top quark with the electroweak gauge bosons is made in the non-linear Chiral Lagrangian approach. Bounds on the anomalous dimension four terms are obtained from their…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. Larios , Ehab Malkawi , C. -P. Yuan

The purpose of the present discussion is to supplement the talk, by B.~Saghai at this workshop, on the study of the electromagnetic production of strangeness on the nucleon based upon effective Lagrangian methods. Here we focus on the…

Nuclear Theory · Physics 2011-04-15 T. Mizutani