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Related papers: Vector-like Singlet Quarks: a Roadmap

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We study the patterns of flavour violation in renormalisable extensions of the Standard Model (SM) that contain vector-like quarks (VLQs) in a single complex representation of either the SM gauge group $G_{SM}$ or $G_{SM}' = G_{SM} \times…

High Energy Physics - Phenomenology · Physics 2017-05-24 Christoph Bobeth , Andrzej J. Buras , Alejandro Celis , Martin Jung

In this talk we emphasise the importance of vector-like quarks (VLQs) and their potential to solve some of the open questions of the Standard Model. These are, in some sense minimal extensions of the Standard Model, that can be probed in…

High Energy Physics - Phenomenology · Physics 2022-08-16 Gustavo Castelo Branco , M. N. Rebelo

We show how a novel fine-tuning problem present in the Standard Model can be solved through the introduction of a single flavour symmetry G, together with three $Q = - 1/3$ quarks, three $Q = 2/3$ quarks, as well as a complex singlet…

High Energy Physics - Phenomenology · Physics 2017-08-02 Francisco J. Botella , G. C. Branco , Miguel Nebot , M. N. Rebelo , J. I. Silva-Marcos

We propose a Vector-like quark (VLQ) model constrained by the requirement of perturbative unitarity. In this scenario, the neutral and charged couplings of the new heavy VLQs to SM quarks and bosons are strictly related. We derive the…

High Energy Physics - Phenomenology · Physics 2022-02-15 E. Accomando , J. Brannigan , J. Gunn , Y. Huyan , S. Mulligan

There are two strong arguments in favor of vector-like leptons and quarks: Flavor Democracy call for them, and E6 GUT predicts existence of iso-singlet quarks and iso-doublet leptons. Vector-like quarks (VLQ) are extensively searched by…

High Energy Physics - Phenomenology · Physics 2022-07-22 Feyza Baspehlivan , Burak Dagli , Osman Emre Delialioglu , Saleh Sultansoy

Vector-like Quarks (VLQs) are potential signatures of physics beyond the Standard Model at the TeV energy scale and major efforts have been put forward at both ATLAS and CMS experiments in search of these particles. In order to make these…

High Energy Physics - Phenomenology · Physics 2020-07-01 Avik Roy , Nikiforos Nikiforou , Nuno Castro , Timothy Andeen

We examine the prospects for LHC discovery of SU(2)_L singlet vector-like quarks that obey Minimal Flavour Violation (MFV) and are consistent with lower energy phenomenology. We study models where the vector-like quarks have the same…

High Energy Physics - Phenomenology · Physics 2010-08-18 Jonathan M. Arnold , Bartosz Fornal , Michael Trott

The Nelson-Barr mechanism to solve the strong CP problem requires vector-like quarks (VLQs) to transmit the spontaneous CP breaking to the SM. We study the scenario where only these VLQs are within reach at the TeV scale while the…

High Energy Physics - Phenomenology · Physics 2020-09-02 A. L. Cherchiglia , C. C. Nishi

Recent high precision determinations of $V_{us}$ and $V_{ud}$ indicate towards anomalies in the first row of the CKM matrix. Namely, determination of $V_{ud}$ from superallowed beta decays and of $V_{us}$ from kaon decays imply a violation…

High Energy Physics - Phenomenology · Physics 2021-10-27 Benedetta Belfatto , Zurab Berezhiani

Vector-like quarks have been of interest for a plethora of experimentally motivated reasons and have come under increased investigation recently due to their inclusion to the Standard Model (SM) appreciably improving global fits to several…

High Energy Physics - Phenomenology · Physics 2022-07-12 Shyam Balaji

Vector-Like Quarks (VLQs) are predicted by several theoretical scenarios of new physics and, having colour quantum numbers, can copiously be produced at the Large Hadron Collider (LHC), so long that their mass is in the testable kinematic…

High Energy Physics - Phenomenology · Physics 2018-07-25 Alexandra Carvalho , Stefano Moretti , Dermot O'Brien , Luca Panizzi , Hugo Prager

We deduce pertinent relations between the elements of the CKM matrix, and find that not all of these are totally compatible with experiment and/or the assumption of the $3 \times 3$ unitarity. We identify complex phases in the CKM-elements…

High Energy Physics - Phenomenology · Physics 2026-03-23 Francisco Albergaria , Francisco J. Botella , G. C. Branco , José Filipe Bastos , J. I. Silva-Marcos

Vector-like quarks (VLQs) that are partners of the heavy top and bottom quarks are predicted in many extensions of the Standard Model (SM). We explore the possibility that these states could explain not only the longstanding anomaly in the…

High Energy Physics - Phenomenology · Physics 2016-03-23 Andrei Angelescu , Abdelhak Djouadi , Grégory Moreau

The inert doublet model (IDM), a minimal extension of the Standard Model (SM), provides a scalar dark matter (DM) candidate that belongs to the additional Higgs doublet. The model faces challenges in achieving the correct relic abundance…

High Energy Physics - Phenomenology · Physics 2025-05-20 Prasanta Kumar Das , Shyamashish Dey , Saumyen Kundu , Santosh Kumar Rai

The Standard Model of particle physics explains many natural phenomena yet remains incomplete. Vectorlike quarks and leptoquarks lie at the heart of many extensions to the Standard Model seeking to address the hierarchy problem, or the…

High Energy Physics - Experiment · Physics 2026-02-02 Elin Bergeaas Kuutmann

We study a model with a down-type SU(2) singlet vector-like quark (VLQ) as a minimal extension of the standard model (SM). In this model, flavor changing neutral currents (FCNCs) arise at tree level and the unitarity of the $3\times 3$…

High Energy Physics - Phenomenology · Physics 2019-12-06 Takuya Morozumi , Yusuke Shimizu , Shunya Takahashi , Hiroyuki Umeeda

Vector-like quarks (VLQs) are attractive extensions to the Standard Model. They mix with the SM quarks and can lead to rich phenomenology. Determination of VLQ's interaction structure with the SM is then an important issue, which can be…

High Energy Physics - Phenomenology · Physics 2019-02-20 Hang Zhou , Ning Liu

The elucidation of the nature of new phenomena requires a multi-pronged approach to understand the essential physics that underlies it. As an example, we study the simplified model containing a new scalar singlet accompanied by vector-like…

High Energy Physics - Phenomenology · Physics 2017-03-08 Anke Biekötter , JoAnne L. Hewett , Jong Soo Kim , Michael Krämer , Thomas G. Rizzo , Krzysztof Rolbiecki , Jamie Tattersall , Torsten Weber

The VuQ model involves the addition of a vector isosinglet up-type quark to the standard model. In this model the full CKM quark mixing matrix is 4 X 3. Using present flavor-physics data, we perform a fit to this full CKM matrix, looking…

High Energy Physics - Phenomenology · Physics 2016-03-10 Ashutosh Kumar Alok , Subhashish Banerjee , Dinesh Kumar , S. Uma Sankar , David London

A search is presented for heavy vector-like quarks (VLQs) that couple only to light quarks in proton-proton collisions at $\sqrt{s} =$ 8 TeV at the LHC. The data were collected by the CMS experiment during 2012 and correspond to an…

High Energy Physics - Experiment · Physics 2018-04-18 CMS Collaboration
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