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Related papers: LHC bounds on coloured scalars

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We study the prospect of measuring the electroweak quantum numbers of beyond the Standard Model (SM) color sextet particles that decay into same-sign top quark pairs. Among these particles, the color sextet scalars give rise to top quarks…

High Energy Physics - Phenomenology · Physics 2023-09-21 Soubhik Kumar , Rafiqul Rahaman , Ritesh K. Singh

We consider a simple extension of the electroweak theory, incorporating one $SU(2)_L$ doublet of colour-octet scalars with Yukawa couplings satisfying the principle of minimal flavour violation. Using the HEPfit package, we perform a global…

High Energy Physics - Phenomenology · Physics 2022-05-12 V. Miralles , O. Eberhardt , H. Gisbert , A. Pich , J. Ruiz-Vidal

The null search for the Higgs boson at the Tevatron implies strong constraints on heavy colored particles that increase the gluon-fusion induced production rate of the Higgs. We investigate the implications of the Tevatron exclusion limit…

High Energy Physics - Phenomenology · Physics 2011-05-13 Radja Boughezal

One possible extension of the Standard Model scalar sector includes SU(2)_L doublet scalars that are color octets rather than singlets. We focus on models in which the couplings to fermions are consistent with the principle of minimal…

High Energy Physics - Phenomenology · Physics 2009-07-24 Chul Kim , Thomas Mehen

The scalar sector of the minimal Left-Right model at TeV scale is revisited in light of the large quartic coupling needed for a heavy flavor-changing scalar. The stability and perturbativity of the effective potential is discussed and…

High Energy Physics - Phenomenology · Physics 2016-08-17 Alessio Maiezza , Miha Nemevšek , Fabrizio Nesti

We discuss the properties and LHC phenomenology of a potentially discoverable heavy scalar boson ($s$) that arises in the context of the renormalizable coloron model; the model also contains a light scalar, $h$, identifiable with the 125…

High Energy Physics - Phenomenology · Physics 2014-07-23 R. Sekhar Chivukula , Arsham Farzinnia , Jing Ren , Elizabeth H. Simmons

The LHC is now studying in detail the couplings of the Higgs boson in order to determine if there is new physics. Many recent studies have examined the available fits to Higgs couplings from the perspective of constraining two Higgs doublet…

High Energy Physics - Phenomenology · Physics 2016-10-12 Li Cheng , German Valencia

We show that production of the Higgs boson through gluon-fusion may be suppressed in the presence of colored scalars. Substantial destructive interference between the top quark diagrams and colored scalar diagrams is possible due to…

High Energy Physics - Phenomenology · Physics 2013-05-30 Bogdan A. Dobrescu , Graham D. Kribs , Adam Martin

We propose that the possible 750 GeV diphoton excess can be explained in the color-octet neutrino mass model extended with a scalar singlet $\Phi$. The model generally contains $N_s$ species of color-octet, electroweak doublet scalars $S$…

High Energy Physics - Phenomenology · Physics 2016-05-04 Ran Ding , Zhi-Long Han , Yi Liao , Xiao-Dong Ma

We study theoretical constraints on a model whose scalar sector contains one color octet and one or two color singlet $SU(2)_L$ doublets. Using the unitarity of the theory, we constrain the parameters of the scalar potential for the first…

High Energy Physics - Phenomenology · Physics 2019-09-04 Li Cheng , Otto Eberhardt , Christopher W. Murphy

We consider the framework of flavoured leptoquarks, in models with scalar or vector leptoquarks, and look for constraints to the parameter space of these models. Using primarily direct searches at the Large Hadron Collider (LHC) and…

High Energy Physics - Phenomenology · Physics 2024-03-01 Ivo de Medeiros Varzielas , Amartya Sengupta

We demonstrate that flavour-changing neutral currents in the top sector, mediated by leptophilic scalars at the electroweak scale, can easily arise in scenarios of new physics, and in particular in composite Higgs models. We moreover show…

High Energy Physics - Phenomenology · Physics 2020-10-14 Nuno Castro , Mikael Chala , Ana Peixoto , Maria Ramos

We study the bounds on minimal lepton flavour violation in the context of Type-III see-saw imposed by LHC Run I search for events which contain two charged leptons (either electron or muons of equal or opposite sign), two jets from a…

High Energy Physics - Phenomenology · Physics 2017-08-30 Nuno Rosa Agostinho , O. J. P. Eboli , M. C. Gonzalez-Garcia

We explore the potential for discovery of an exotic color sextet scalar in same-sign top quark pair production in early running at the LHC. We present the first phenomenological analysis at colliders of color sextet scalars with full top…

High Energy Physics - Phenomenology · Physics 2012-01-25 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Gabe Shaughnessy , Hao Zhang

The renormalizable coloron model is the minimal extension of the standard model color sector, in which the color gauge group is enlarged to SU(3)_{1c} x SU(3)_{2c}. In this paper we discuss the constraints on this model derived from the…

High Energy Physics - Phenomenology · Physics 2014-03-06 R. Sekhar Chivukula , Arsham Farzinnia , Jing Ren , Elizabeth H. Simmons

We demonstrate that in a recently proposed unified leptoquark model based on the gauge group $SU(4)_C\times SU(2)_L \times U(1)_R$ significant deviations from the Standard Model values of $R_K$ and $R_{K^*}$ can be accommodated without any…

High Energy Physics - Phenomenology · Physics 2021-01-07 Thomas Faber , Matěj Hudec , Helena Kolešová , Yang Liu , Michal Malinský , Werner Porod , Florian Staub

The contributions into radiative correction parameters S, T, U from scalar leptoquark and scalar gluon doublets are investigated in the minimal four color symmetry model. It is shown that the current experimental data on S, T, U allow the…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. D. Smirnov

Majorana neutrino mass models with a scale of lepton number violation (LNV) of order TeV potentially lead to signals at the LHC. Here, we consider an extension of the standard model with a coloured octet fermion and a scalar leptoquark.…

High Energy Physics - Phenomenology · Physics 2019-06-26 E. Carquin , J. C. Helo , M. Hirsch , N. A. Neill

The Large Hadron Collider(LHC) has completed its run at 8 TeV with the experiments ATLAS and CMS having collected about 25 $\rm fb^{-1}$ of data each. Discovery of a light Higgs boson, coupled with lack of evidence for supersymmetry at the…

High Energy Physics - Phenomenology · Physics 2015-06-17 Genevieve Belanger , Diptimoy Ghosh , Rohini Godbole , Monoranjan Guchait , Dipan Sengupta

We propose a new mechanism to generate the electroweak scale within the framework of QCD, which is extended to include conformally invariant scalar degrees of freedom belonging to a larger irreducible representation of $SU(3)_c$. The…

High Energy Physics - Phenomenology · Physics 2014-09-02 Jisuke Kubo , Kher Sham Lim , Manfred Lindner