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Related papers: Four Statements about the Fourth Generation

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This is a personal summary of points made during, and arising from the symposium, drawing largely from the talks presented there. The Standard Model is doing fine, including QCD, the electroweak sector and flavour physics. The good news is…

High Energy Physics - Phenomenology · Physics 2015-06-17 John Ellis

A fourth generation of quarks, if it exist, may provide sufficient CP violation for the baryon asymmetry of the Universe. We estimate the neutron electric dipole moment in the presence of a fourth generation, and find it would be dominated…

High Energy Physics - Phenomenology · Physics 2013-05-29 Junji Hisano , Wei-Shu Hou , Fanrong Xu

In the Standard Model, three discovered generations of leptons and quarks are known to date. However, speculations about existence of next generations have a strong foothold. In this study, we sequentially extrapolate the Standard Model to…

High Energy Physics - Phenomenology · Physics 2025-10-30 Ramkrishna Joshi , Riddhiman Roy

With an expected rate of about one event per 100,000 top-quark pairs, four top-quark final states very rarely arise at the LHC. Though scarce, they offer a unique window onto top-quark compositeness, self-interactions and more generically,…

High Energy Physics - Phenomenology · Physics 2021-10-14 Luc Darmé , Benjamin Fuks , Fabio Maltoni

We consider the bounds for the values of higgs mass $M_H$ and of the mass of the extra quarks and leptons $M_{extra}$ derived from the stability of vacuum and from the absence of Landau pole in Higgs potential. We find that in the case of…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. B. Nielsen , A. V. Novikov , V. A. Novikov , M. I. Vysotsky

There exist tree-level generalizations of the Type-I and Type-III seesaw mechanisms that realize neutrino mass via low-energy effective operators with d>5. However, these generalizations also give radiative masses that can dominate the…

High Energy Physics - Phenomenology · Physics 2015-12-01 Kristian L. McDonald

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

Starting in two years from now, particle physics will enter a new regime in terms of energies and luminosities, thanks to the Large Hadron Collider (LHC) at CERN. This report summarizes the status of the preparations, both for the machine…

High Energy Physics - Experiment · Physics 2007-05-23 Guenther Dissertori

Naturalness arguments suggest that the stop sector is within reach of the Large Hadron Collider (LHC). We investigate how the observation of a third generation squark signal could predict masses and discovery modes of other supersymmetric…

High Energy Physics - Phenomenology · Physics 2018-06-15 Aaron Pierce , Bibhushan Shakya

We study the impact of machine-learning algorithms on LHC searches for leptoquarks in final states with hadronically decaying tau leptons, multiple $b$-jets, and large missing transverse momentum. Pair production of scalar leptoquarks with…

High Energy Physics - Phenomenology · Physics 2024-03-12 Ernesto Arganda , Daniel A. Díaz , Andres D. Perez , Rosa M. Sandá Seoane , Alejandro Szynkman

The success of the first three years of operations of the LHC at center-of-mass energies of 7 and 8 TeV radically changed the landscape of searches for new physics beyond the standard model and our very way of thinking about its possible…

High Energy Physics - Experiment · Physics 2015-06-02 Greg Landsberg

Chapter 4 in High-Luminosity Large Hadron Collider (HL-LHC). The Large Hadron Collider (LHC) is one of the largest scientific instruments ever built. Since opening up a new energy frontier for exploration in 2010, it has gathered a global…

We study dynamical electroweak symmetry breaking with a fourth generation within the $Z_n$ orbifolded $AdS_5\otimes S^5$ framework. A realistic $Z_7$ example is discussed. The initial theory reduces dynamically, due to the induced…

High Energy Physics - Phenomenology · Physics 2015-05-27 Chiu Man Ho , Pham Q. Hung , Thomas W. Kephart

We present a short overview of recent work on the topic of flavour violation in the presence of a sequential fourth generation (4G) of quarks and leptons. We discuss the implications of this simple extension of the Standard Model (SM3) for…

High Energy Physics - Phenomenology · Physics 2010-11-29 Tillmann Heidsieck

In this review a history of development of electron accelerators for HEP and for LSs in Russia is presented.

Accelerator Physics · Physics 2009-06-10 E. G. Bessonov

We present the discovery prospects for a Z' resonance and some expected results for Z' diagnostic measurements at the LHC. The discovery reach is highly dependent on the energy and luminosities that may be attained at the LHC, and a number…

High Energy Physics - Phenomenology · Physics 2009-10-10 Ross Diener , Stephen Godfrey , Travis A. W. Martin

We study Higgs-radion mixing in a warped extra dimensional model with Standard Model fields in the bulk, and we include a fourth generation of chiral fermions. The main problem with the fourth generation is that, in the absence of…

High Energy Physics - Phenomenology · Physics 2013-05-30 Mariana Frank , Beste Korutlu , Manuel Toharia

We explain the current Large Hadron Collider (LHC) data pointing to the discovery of a neutral Higgs boson in the context of a 4-Dimensional Composite Higgs Model (4DCHM). The full particle spectrum of this scenario is derived without any…

High Energy Physics - Phenomenology · Physics 2013-04-18 D. Barducci , A. Belyaev , M. S. Brown , S. De Curtis , S. Moretti , G. M. Pruna

We use sampling techniques to find robust constraints on the masses of a possible fourth sequential fermion generation from electroweak oblique variables. We find that in the case of a light (115 GeV) Higgs from a single electroweak…

High Energy Physics - Phenomenology · Physics 2015-06-05 Leo Bellantoni , Jens Erler , Jonathan J. Heckman , Enrique Ramirez-Homs

Data taking at the LHC is the beginning of a new era in particle physics which will lead us towards understanding the completion of the Standard Model at and beyond the TeV scale. I discuss different approaches to new physics searches:…

High Energy Physics - Phenomenology · Physics 2011-02-28 Tilman Plehn
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