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Related papers: Closing in on a perturbative fourth generation

200 papers

We consider the phenomenology of the fourth generation heavy quarks which would be pair produced at the LHC. We show that if such a quark with a mass in the phenomenologically interesting range of 400 GeV--600 GeV decays to a light quark…

High Energy Physics - Phenomenology · Physics 2013-02-25 David Atwood , Sudhir Kumar Gupta , Amarjit Soni

We study the phenomenological viability of chiral extensions of the Standard Model, with new chiral fermions acquiring their mass through interactions with a single Higgs. We examine constraints from electroweak precision tests, Higgs…

High Energy Physics - Phenomenology · Physics 2023-12-27 Daniele Barducci , Luca Di Luzio , Marco Nardecchia , Claudio Toni

Determining if the SM-like Higgs is part of an extended Higgs sector is the most important question to be asked after discovery. A light charged Higgs boson with mass smaller than the sum of top and bottom quarks is naturally allowed in…

High Energy Physics - Phenomenology · Physics 2023-07-05 Disha Bhatia , Nishita Desai , Siddharth Dwivedi

Unification at M_{GUT}\sim 3\times 10^{16} GeV of the three Standard Model (SM) gauge couplings can be achieved by postulating the existence of a pair of vectorlike fermions carrying SM charges and masses of order 300 GeV -- 1 TeV. The…

High Energy Physics - Phenomenology · Physics 2014-11-20 Ilia Gogoladze , Bin He , Qaisar Shafi

The recent announcement of a discovery of a possible Higgs-like particle -its spin and parity is yet to be determined- at the LHC with a mass of 126 GeV necessitates a fresh look at the nature of the electroweak symmetry breaking, in…

High Energy Physics - Phenomenology · Physics 2013-09-09 Pham Q. Hung

The first evidence of new strong interactions may be a sufficiently massive fourth family observed at the LHC. The fourth family masses, of the leptons in particular, are constrained by the electroweak precision data, and this leads to…

High Energy Physics - Phenomenology · Physics 2009-11-11 B. Holdom

We assess the current state of searches at the LHC for additional Higgs bosons in light of both direct limits and indirect bounds coming from coupling measurements of the Standard Model-like Higgs boson. Given current constraints, we…

High Energy Physics - Phenomenology · Physics 2015-04-21 Nathaniel Craig , Francesco D'Eramo , Patrick Draper , Scott Thomas , Hao Zhang

Accelerator searches for new resonances have a long-standing history of discoveries that have driven advances in our understanding of nature. Since 2010, the Large Hadron Collider (LHC) has probed previously inaccessible energy scales,…

High Energy Physics - Experiment · Physics 2024-04-24 Barbara Clerbaux , Carl Gwilliam

The search for heavy Higgs bosons at the LHC represents an intense experimental program, carried out by the ATLAS and CMS collaborations, which includes the hunt for invisible Higgs decays and dark matter candidates. No significant…

High Energy Physics - Phenomenology · Physics 2018-03-08 Ernesto Arganda , J. Lorenzo Díaz-Cruz , Nicolás Mileo , Roberto A. Morales , Alejandro Szynkman

A search for the Standard Model Higgs boson in proton-proton collisions at a center-of-mass energy of 7 TeV is presented in the decay channel H-->ZZ-->2l2n. The search is conducted by the CMS experiment with data accumulated during the 2010…

High Energy Physics - Experiment · Physics 2019-08-13 Daniele Trocino

We study the potential of the current Large Hadron Collider (LHC) 7 TeV run to search for heavy, colored vector-like fermions, which are assumed to carry a conserved Z2 quantum number forcing them to be pair-produced. Each fermion is…

High Energy Physics - Phenomenology · Physics 2015-05-27 Maxim Perelstein , Jing Shao

We look for minimal extensions of Standard Model with vector like fermions leading to precision unification of gauge couplings. Constraints from proton decay, Higgs stability and perturbativity are considered. The simplest models contain…

High Energy Physics - Phenomenology · Physics 2018-05-17 Biplob Bhattacherjee , Pritibhajan Byakti , Ashwani Kushwaha , Sudhir K Vempati

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

In light of recent experimental results, we present updated bounds on the lightest Higgs boson mass in the Standard Model (SM) and in the Minimal Supersymmetric extension of the Standard Model (MSSM). The vacuum stability lower bound on the…

High Energy Physics - Phenomenology · Physics 2007-05-23 David Dooling , Kyungsik Kang , Sin Kyu Kang

Searching for new Higgs particle beyond the observed light Higgs boson h(125GeV) will unambiguously point to new physics beyond the standard model. We study the resonant production of a CP-even heavy Higgs state $H^0$ in the di-Higgs…

High Energy Physics - Phenomenology · Physics 2018-06-26 Jing Ren , Rui-Qing Xiao , Maosen Zhou , Yaquan Fang , Hong-Jian He , Weiming Yao

In the context of two-Higgs doublet models, we explore the possibility of searching for heavy Higgs bosons in the $t \bar t Z$ and $t bW$ final states. We develop realistic analyses strategies and in the case of the $t \bar t Z$ channel…

High Energy Physics - Phenomenology · Physics 2018-10-17 Ulrich Haisch , Giacomo Polesello

We present the results of calculations for the process gamma gamma -> W + 2 fermions at a future Photon Linear Collider (PLC). The calculations include at the same time the next-to-leading order Higgs signal and the complete tree level…

High Energy Physics - Phenomenology · Physics 2009-10-31 E. Boos , V. Ilyin , D. Kovalenko , T. Ohl , A. Pukhov , M. Sachwitz , H. J. Schreiber

We study the effect of a potential fourth quark generation on the upper and lower Higgs boson mass bounds. This investigation is based on the numerical evaluation of a chirally invariant lattice Higgs-Yukawa model emulating the same…

High Energy Physics - Lattice · Physics 2011-02-03 P. Gerhold , K. Jansen , J. Kallarackal

Attention is drawn to the several 2-3 $\sigma$ "anomalies" in B, $B_s$ mixings and decays involving CP-observables. Perhaps the most interesting theoretical scenario that could cause such effects is based on warped extra-dimensional models…

High Energy Physics - Phenomenology · Physics 2009-07-14 Amarjit Soni

Condensates of colored fermions driving electroweak symmetry breaking could give rise to a light pseudoscalar that would show up in the Higgs search at the LHC. The branching ratios of its decay will distinguish it from the Higgs and…

High Energy Physics - Phenomenology · Physics 2012-03-07 B. Holdom