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Related papers: A Higgs Conundrum with Vector Fermions

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Pair production of new vector-like quarks in $pp$ collisions is considered model independent as it is usually dominated by QCD production. Nonetheless, the presence of a new massive color octet (heavy gluon) in some composite Higgs models…

High Energy Physics - Phenomenology · Physics 2015-12-16 Juan Pedro Araque , Nuno Filipe Castro , Jose Santiago

Studying the properties of the Higgs boson can be an important window to explore the physics beyond the Standard Model (SM). In this work, we present studies on the implications of the Higgs precision measurements at future Higgs Factories.…

High Energy Physics - Phenomenology · Physics 2019-06-26 Ning Chen , Jiayin Gu , Tao Han , Honglei Li , Zhen Liu , Huayang Song , Shufang Su , Wei Su , Yongcheng Wu , Jin Min Yang

The Higgs low-energy theorem gives a simple and elegant way to estimate the couplings of the Higgs boson to massless gluons and photons induced by loops of heavy particles. We extend this theorem to take into account possible nonlinear…

High Energy Physics - Phenomenology · Physics 2015-03-20 M. Gillioz , R. Grober , C. Grojean , M. Muhlleitner , E. Salvioni

Beyond Standard Model theories describing the electro-weak sector must exhibit a large separation of scales (or "walking") to account for a light, 125 GeV Higgs boson and the fact that so far no other resonances have been observed. Large…

High Energy Physics - Phenomenology · Physics 2018-10-04 Oliver Witzel , Anna Hasenfratz , Claudio Rebbi

After the discovery of a Higgs boson at the LHC, the next important step is to measure its couplings to fermions and bosons to unravel its true nature. In order to ultimately test the shape of the scalar potential that triggers the…

High Energy Physics - Phenomenology · Physics 2014-08-26 Julien Baglio

Several extensions of the Standard Model require the burden of electroweak symmetry breaking to be shared by multiple states or sectors. This leads to the possibility of the top quark interacting with a scalar more strongly than it does…

High Energy Physics - Phenomenology · Physics 2009-10-30 Michael Spira , James D. Wells

We show that the leading coupling between a shift symmetric inflaton and the Standard Model fermions leads to an induced electroweak symmetry breaking due to particle production during inflation, and as a result, a unique oscillating…

High Energy Physics - Phenomenology · Physics 2020-01-29 Anson Hook , Junwu Huang , Davide Racco

We derive new constraints on light vectors coupled to Standard Model (SM) fermions, when the corresponding SM current is broken by the chiral anomaly. Cancellation of the anomaly by heavy fermions results, in the low-energy theory, in…

High Energy Physics - Phenomenology · Physics 2021-02-05 Jeff A. Dror , Robert Lasenby , Maxim Pospelov

Higgs production from gluon fusion is sensitive to the properties of heavy colored fermions and to the Yukawa couplings, (Y_F M_F)/v, of these particles to the Higgs boson. We compute the two--loop, ${\cal O}((Y_F M_F)^3/v^3)$ contributions…

High Energy Physics - Phenomenology · Physics 2014-02-13 Sally Dawson , Elisabetta Furlan

Many extensions of the Standard Model postulate the existence of new weakly coupled particles, the top partners, at or below the TeV scale. The role of the top partners is to cancel the quadratic divergence in the Higgs mass parameter due…

High Energy Physics - Phenomenology · Physics 2014-07-23 Marco Farina , Maxim Perelstein , Nicolas Rey-Le Lorier

Performing a fit to all publicly available data, we analyze the extent to which the latest results from the LHC and Tevatron constrain the couplings of the Higgs boson-like state at ~ 125 GeV. To this end we assume that only Standard Model…

High Energy Physics - Phenomenology · Physics 2015-06-12 G. Belanger , B. Dumont , U. Ellwanger , J. F. Gunion , S. Kraml

This review is based on the talk presented at the SUSY 2012 (Beijing). The new particle around 125 GeV observed at the Large Hadron Collider (LHC) is almost consistent with the standard model Higgs boson, except that the diphoton decay mode…

High Energy Physics - Phenomenology · Physics 2012-12-24 Jung Chang , Kingman Cheung , Po-Yan Tseng , Tzu-Chiang Yuan

We study the low energy phenomenology of the little Higgs model. We first discuss the linearized effective theory of the "littlest Higgs model" and study the low energy constraints on the model parameters. We identify sources of the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Tao Han , Heather E. Logan , Bob McElrath , Lian-Tao Wang

We consider a scenario of a composite Higgs arising from a strong sector. We assume that the lowest lying composite states are the Higgs scalar doublet and a massive vector triplet, whose dynamics below the compositeness scale are described…

High Energy Physics - Phenomenology · Physics 2018-01-03 A. E. Cárcamo Hernández , Bastián Díaz Sáez , Claudio O. Dib , Alfonso Zerwekh

We perform the fit of electroweak precision observables within the Standard Model with a 126 GeV Higgs boson, compare the results with the theoretical predictions and discuss the impact of recent experimental and theoretical improvements.…

High Energy Physics - Phenomenology · Physics 2015-06-16 Marco Ciuchini , Enrico Franco , Satoshi Mishima , Luca Silvestrini

Some extensions of the Standard Model suggest existence of vectorlike fermions whose mass $M$ can be by up to several orders of magnitude larger than the electroweak scale $v$, and with the Higgs mechanism providing only a small part $m$ of…

High Energy Physics - Phenomenology · Physics 2015-09-02 M. B. Voloshin

After the Higgs discovery, the question of whether particles beyond those of the Standard Model exist is more pressing than ever. In this context, the scalar sector is particularly promising, since it lies at the core of the internal…

High Energy Physics - Phenomenology · Physics 2026-05-07 Andreas Crivellin , Saiyad Ashanujjaman , Sumit Banik , Siddharth P. Maharathy , Guglielmo Coloretti

First, we study the fit of the Higgs boson rates, based on all the latest collider data, in the effective framework for any Extra-Fermion(s) [EF]. The best-fit results are presented in a generic formalism allowing to apply those for the…

High Energy Physics - Phenomenology · Physics 2013-03-19 G. Moreau

The loop induced coupling of an intermediate mass Higgs boson to two photons is a sensitive and unique measure for precision tests of physics beyond the Standard Model. In this work we summarize recent results on the expected precision of…

High Energy Physics - Phenomenology · Physics 2009-10-31 Michael Melles

We explore models of new physics that can give rise to large (100% or more) enhancements to the rate of Higgs decay to $Z\gamma$ while still being consistent with other measurements. We show that this is impossible in simple models with one…

High Energy Physics - Phenomenology · Physics 2021-11-22 Paul Archer-Smith , Daniel Stolarski , Roberto Vega-Morales