Journal of High Energy Physics

, 2019:134 | Cite as

Exotic decays of top partners with charge 5/3: bounds and opportunities

  • Ke-Pan Xie
  • Giacomo Cacciapaglia
  • Thomas FlackeEmail author
Open Access
Regular Article - Experimental Physics


Exotic decays of top partners in new bosons are the norm in realistic models of a composite Higgs. We focus on the custodial charge-5/3 partner, which normally decays exclusively into tW+. The new channels include a colour-sextet, X5/3\( \overline{b} \)π6, as well as singly and doubly charged scalars, X5/3→ t𝜙+, b𝜙++. We use existing same-sign lepton searches to show that the new final states are constrained at the same level as the standard one. At the same time, exotic final states also offer opportunities for improvement: examples include a hard photon in X5/3→ t𝜙+→ tW+γ decays, and top-rich channels which arises in several exotic X5/3 decays.


Exotics vector-like quarks Beyond Standard Model Hadron-Hadron scattering (experiments) same charge top pair 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited


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Copyright information

© The Author(s) 2019

Authors and Affiliations

  1. 1.Center for Theoretical Physics, Department of Physics and AstronomySeoul National UniversitySeoulKorea
  2. 2.University of Lyon, Universit́e Claude Bernard Lyon 1LyonFrance
  3. 3.Institut de Physique des 2 Infinis de Lyon (IP2I), CNRS/IN2P3 UMR5822VilleurbanneFrance
  4. 4.Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS)DaejeonKorea

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