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Related papers: Doubling down on down-type diquarks

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Minimal Flavour Violation hypothesis can provide an attractive framework for Dark Matter (DM). We consider scalar DM candidates carrying flavour quantum numbers and whose representation under the flavour group guarantees DM stability. They…

High Energy Physics - Phenomenology · Physics 2015-06-15 Laura Lopez-Honorez , Luca Merlo

This is a brief pedagogic introduction to searches for new physics with top quarks. It covers indirect searches for heavy new particles based on standard model effective theory and direct searches for new signatures of a light hidden…

High Energy Physics - Phenomenology · Physics 2019-12-05 Susanne Westhoff

We investigate the sensitivity of the LHC to flavour-changing neutral current interactions involving the top quark and a photon using a model-independent effective field theory framework, focusing on two complementary processes: single top…

High Energy Physics - Phenomenology · Physics 2026-02-17 Benjamin Fuks , Sumit K. Garg , A. Hammad , Adil Jueid

A number of years ago, low-energy constraints on scalar diquarks, particles that couple to two quarks, were examined. It was found that the two most weakly-constrained diquarks are $D^u$ and $D^d$, colour antitriplets that couple to…

High Energy Physics - Phenomenology · Physics 2020-08-26 Bruna Pascual-Dias , Pratishruti Saha , David London

The Large Hadron Collider can do precision physics at a level that is competitive with electroweak precision constraints when probing physics beyond the Standard Model. We present a simple yet general parameterization of the effect of an…

High Energy Physics - Phenomenology · Physics 2013-11-27 J. de Blas , M. Chala , Jose Santiago

We present new linear relations among the masses of S-wave tetraquarks with either one flavour ($QQ \bar Q \bar Q$) or two ($QQ\bar q \bar q$). Because the relations are sensitive to the hidden-colour, spin, and spatial degrees of freedom,…

High Energy Physics - Phenomenology · Physics 2023-12-01 Muhammad Naeem Anwar , Timothy J. Burns

We study direct searches of additional Higgs bosons in multi-top-quarks events at the LHC with the collision energy of 14 TeV as well as the International Linear Collider (ILC) with the collision energy of 1 TeV. As a benchmark model, we…

High Energy Physics - Phenomenology · Physics 2015-05-20 Hiroshi Yokoya

A high energy muon collider can provide new and complementary discovery potential to the LHC or future hadron colliders. Leptoquarks are a motivated class of exotic new physics models, with distinct production channels at hadron and lepton…

High Energy Physics - Phenomenology · Physics 2021-11-10 Pouya Asadi , Rodolfo Capdevilla , Cari Cesarotti , Samuel Homiller

We consider constraints from flavor physics on two-Higgs-doublet models (2HDM) with general, flavor-diagonal, Yukawa couplings. Analyzing the charged Higgs contribution to different observables, we find that $b\to s\gamma$ transitions and…

High Energy Physics - Phenomenology · Physics 2010-02-19 Farvah Mahmoudi , Oscar Stål

A modest extension of the Standard Model by two additional Higgs doublets - the Higgs Troika Model - can provide a well-motivated scenario for successful baryogenesis if neutrinos are Dirac fermions. Adapting the "Spontaneous Flavor…

High Energy Physics - Phenomenology · Physics 2022-03-01 Hooman Davoudiasl , Ian M. Lewis , Matthew Sullivan

Heavy vector-like quarks coupled to a scalar $S$ will induce a coupling of this scalar to gluons and possibly (if electrically charged) photons. The decay of the heavy quark into $Sq$, with $q$ being a Standard Model quark, provides, if…

High Energy Physics - Phenomenology · Physics 2016-11-29 Shankha Banerjee , Daniele Barducci , Geneviève Bélanger , Cédric Delaunay

The next generation of experiments in particle physics will for the first time systematically test flavor physics models based on flavon fields. Starting from the current quark-flavor constrains on such models we show how the new generation…

High Energy Physics - Phenomenology · Physics 2016-09-21 Martin Bauer , Torben Schell , Tilman Plehn

If the LHC should fail to observe direct signals for new physics, it may become necessary to look for new physics effects in rare events such as flavour-changing decays of the top quark, which, in the Standard Model, are predicted to be too…

High Energy Physics - Phenomenology · Physics 2016-08-09 Debjyoti Bardhan , Gautam Bhattacharyya , Diptimoy Ghosh , Monalisa Patra , Sreerup Raychaudhuri

$B$-physics data and flavor symmetries suggest that leptoquarks can have masses as low as few ${\cal{O}}(\mbox{TeV})$, predominantly decay to third generation quarks, and highlight $pp \to b \mu \mu$ signatures from single production and…

High Energy Physics - Phenomenology · Physics 2018-04-11 Gudrun Hiller , Dennis Loose , Ivan Nisandzic

We study a version of Two Higgs Doublet Models with non-standard flavor violation in the up quark sector. We find branching ratios for the rare top decays $t\to hc$ and $t\to hu$ that are within reach of current and future colliders, while…

High Energy Physics - Phenomenology · Physics 2019-07-17 Wolfgang Altmannshofer , Brian Maddock , Douglas Tuckler

We show that colliders can impose strong constraints on models of dark matter, in particular when the dark matter is light. We analyze models where the dark matter is a fermion or scalar interacting with quarks and/or gluons through an…

High Energy Physics - Phenomenology · Physics 2011-04-05 Jessica Goodman , Masahiro Ibe , Arvind Rajaraman , William Shepherd , Tim M. P. Tait , Hai-Bo Yu

Composite Higgs models, together with partial compositeness, predict the existence of new scalars and vector-like quarks (partners) at and above the TeV scale. Generically, the presence of these additional scalars opens up new decay…

High Energy Physics - Phenomenology · Physics 2022-03-31 Avik Banerjee , Diogo Buarque Franzosi , Gabriele Ferretti

We apply LHC data to constrain a simplified extension of the Standard Model containing a new spin-1 mediator $R$, which does not couple to first generation quarks, and a spinor dark matter particle $\chi$. We recast ATLAS and CMS searches…

High Energy Physics - Phenomenology · Physics 2019-08-14 Manuel Drees , Zhongyi Zhang

Two Higgs-doublet models usually consider an ad-hoc $\mathbb{Z}_2$ discrete symmetry to avoid flavor changing neutral currents. We consider a new class of two Higgs-doublet models where $\mathbb{Z}_2$ is enlarged to the symmetry group…

High Energy Physics - Phenomenology · Physics 2020-02-19 S. Centelles Chuliá , W. Rodejohann , U. J. Saldaña-Salazar

We investigate the collider phenomenology of the standard Hierarchical VEVs Model by proposing a new version, which avoids large flavor changing neutral current interactions, thus, rendering the scale of new physics as low as the…

High Energy Physics - Phenomenology · Physics 2026-01-21 Gauhar Abbas , Neelam Singh