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Related papers: Precision Constraints on Extra Fermion Generations

200 papers

In models with supersymmetry breaking by boundary conditions on an extra dimension it is possible to relate in a quantitative natural way the Fermi scale to the size of the extra dimension. We analyze in detail the compatibility of such…

High Energy Physics - Phenomenology · Physics 2009-11-10 Guido Marandella , Michele Papucci

The dynamics of fermion generations is treated in the framework of the fractional Lagrangian and Hamiltonian in the compact extra dimension. The resulting spectra for u, d, e generations are described by the only mass parameter and slightly…

High Energy Physics - Phenomenology · Physics 2018-01-25 Yu. A. Simonov

This is a pedagogical and self-contained review on obtaining electroweak precision constraints on TeV scale new physics using the effective theory method. We identify a set of relevant effective operators in the standard model and calculate…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zhenyu Han

A brief review is given of precision electroweak physics, and its implications for establishing the standard model and constraining the possibilities for new physics at the TeV scale and beyond.

High Energy Physics - Phenomenology · Physics 2008-11-26 Paul Langacker

The precise measurement of physics observables and the test of their consistency within the standard model (SM) are an invaluable approach, complemented by direct searches for new particles, to determine the existence of physics beyond the…

I summarize recent developments in electroweak precision physics and global fits. Expectations for future measurements, both at lower energies and the energy frontier, are also discussed.

High Energy Physics - Phenomenology · Physics 2021-05-05 Jens Erler

B-decays mediated by both charged currents and neutral currents have provided hints of violation of lepton flavour universality. By assuming an explanation of these anomalies in terms of new physics at the TeV scale affecting the third…

High Energy Physics - Phenomenology · Physics 2018-08-07 Ferruccio Feruglio

We investigate the experimentally allowed parameter space of an extension of the standard model (SM3) by one additional family of fermions. Therefore we extend our previous study of the CKM like mixing constraints of a fourth generation of…

High Energy Physics - Phenomenology · Physics 2010-12-13 Otto Eberhardt , Alexander Lenz , Jürgen Rohrwild

From non-observation at LEP1, a lower mass limit of 45 GeV has been established on any additional sequential fermion beyond the three generations. Precision measurements have further constrained the number of such additional generations,…

High Energy Physics - Phenomenology · Physics 2009-10-28 Gautam Bhattacharyya , Debajyoti Choudhury

Work on electroweak precision calculations and event generators for electroweak physics studies at current and future colliders is summarized.

High Energy Physics - Phenomenology · Physics 2009-03-19 W. Hollik

I review constraints on the Standard Model (SM) Higgs boson from high energy electroweak (EW) precision data. The same data set also strongly limits various mixing effects of hypothetical extra neutral gauge bosons (Z') with the ordinary Z.…

High Energy Physics - Phenomenology · Physics 2009-07-07 Jens Erler

Little Higgs theories are a fascinating new idea to solve the little hierarchy problem by stabilizing the Higgs mass against one-loop quadratically divergent radiative corrections. In this talk I give a brief overview of the idea, focusing…

High Energy Physics - Phenomenology · Physics 2007-05-23 Graham D. Kribs

Extra-dimensional Higgsless models with electroweak symmetry breaking through boundary conditions generically have difficulties with electroweak precision constraints, when the fermions are localized to the ``branes'' in the fifth…

High Energy Physics - Phenomenology · Physics 2010-04-05 Roshan Foadi , Shrihari Gopalakrishna , Carl Schmidt

The evidence for electroweak radiative corrections not contained in $\alpha(m_Z)$ is examined. At low energies there is very strong evidence in the analysis of the unitarity of the CKM matrix. At LEP and collider experiments the current…

High Energy Physics - Phenomenology · Physics 2010-11-01 Alberto Sirlin

The possibility of radiative generation of fermion masses from soft supersymmetry breaking chiral flavor violation is explored. Consistent models are identified and classified. Phenomenological implications for electric dipole moments and…

High Energy Physics - Phenomenology · Physics 2009-10-30 F. M. Borzumati , G. R. Farrar , N. Polonsky , S. Thomas

We study extensions of the Standard Model with general new vector bosons. The full Standard Model gauge symmetry is used to classify the extra vectors and constrain their couplings. We derive the corresponding effective Lagrangian, valid at…

High Energy Physics - Phenomenology · Physics 2025-02-05 F. del Aguila , J. de Blas , M. Perez-Victoria

We review the available constraints on the low energy supersymmetry. The bulk of the electroweak data is well screened from supersymmetric loop effects, due to the structure of the theory, even with superpartners generically light, ${\cal…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. H. Chankowski

We consider an extended electroweak gauge group: SU(2)$_1 \times$ SU(2)$_2 \times$ U(1)$_Y$ where the first and second generation of fermions couple to SU(2)$_1$ and the third generation couples to SU(2)$_2$. Bounds based on heavy gauge…

High Energy Physics - Phenomenology · Physics 2010-12-02 David Muller , Satyanarayan Nandi

After reviewing the key features of the global electroweak fit, I will provide updated results and offer experimental and theoretical contexts. I will also make the case for greater precision and highlight future directions.

High Energy Physics - Phenomenology · Physics 2017-04-28 Jens Erler

In the past decade, electroweak penguin decays have provided a number of precision measurements, turning into one of the most competitive ways to search for New Physics that describe beyond the Standard Model phenomena. An overview of the…

High Energy Physics - Experiment · Physics 2022-09-29 Ulrik Egede , Shohei Nishida , Mitesh Patel , Marie-Hélène Schune