NLO Standard model effective field theory for Higgs and EW precision data

A set of constructs, definitions, and propositions that present a systematic view of the Standard Model Effective Field Theory (SMEFT), i.e. how the influence of higher energy processes is localizable in a few structural properties which can be captured by a handful of Wilson coefficients.Comment: Proceedings for Loops and Legs in Quantum Field Theory, 24-29 April 2016, Leipzig, German

Unstable Particles and Non-Conserved Currents: a Generalization of the Fermion-Loop Scheme

A generalization of the Fermion-Loop scheme is introduced to account for external, non-conserved, currents. Complete Dyson re-summed transitions are introduced, including the contributions from the Higgs-Kibble ghosts in the 't Hooft-Feynman gauge. Running vector boson masses are introduced and their relation with the corresponding complex poles are investigated. It is shown that any S-matrix element takes a very simple form when written in terms of these running masses. A special example of Ward identity, the U(1) Ward identity for single-W, is derived in a situation where all currents are non-conserved and where the top quark mass is not neglected inside loops.Comment: 48 pages(Latex

Recent Theoretical Developments in LEP 2 Physics

Recent theoretical developments in electron-positron annihilation into fermion pairs are summarized. In particular, two-fermion production, DPA for WW signal, single-W production and ZZ signalComment: 6 pages(Latex), 4 figures. To appear in Proceedings of ICHEP2000, Osaka, Japan, 27 July - 2 August 200

Non-Annihilation Processes, Fermion-Loop and QED Radiation

The bulk of large radiative corrections to any process can be obtained by promoting coupling constants to be running ones and by including QED radiation at the leading logarithmic level via structure functions evoluted at some scale. The problem of fixing the proper scale in running coupling constants and in structure functions for non-annihilation processes is briefly addressed and the general solution is analyzed.Comment: 9 pages(Latex), 9 figures. Presented at the 5th International Symposium on Radiative Corrections (RADCOR--2000) Carmel CA, USA, 11--15 September, 200

The Twofold Way, a Short Disquisition of LEP Physics

A condensed survey of various aspects of LEP 1 physics is presented with a critical examination of the ingredients that are available for theoretical predictions. A prototype of comparisons for 2f calculations can be found in hep-ph/9902452.Comment: 16 pages(Latex). To appear in the Proceedings of "XIVth International Workshop: High Energy Physics and Quantum Field Theory (QFTHEP99)", Moscow, Russia, 27 May - 2 June 199

Precision Electroweak Tests of the Standard Model

The study of electron-positron collisions at LEP, together with additional measurements from other experiments, in particular those at SLC and at the Tevatron, has allowed for tests of the electroweak Standard Model with unprecedented accuracy. We review the results of the electroweak precision tests and their implications on the determination of the Standard Model parameters, in particular of the Higgs boson mass, and comment on the constraints for possible new physics effects.Comment: 16 pages 6 figures; to appear in a special issue of Physics Reports dedicated to CERN on the occasion of the laboratory's 50th anniversar