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arXiv · 1806.06018

Probing for Extra Top Yukawa Couplings in Light of $t\bar th(125)$ Observation

Wei-Shu Hou·Masaya Kohda·Tanmoy Modak
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Abstract

The observation of $t\bar th(125)$ production at the Large Hadron Collider (LHC) is the first direct measurement of the top Yukawa coupling. It opens the window on an extra top Yukawa coupling, $ρ_{tt}$, from a second Higgs doublet, without a $Z_2$ symmetry to forbid flavor changing neutral Higgs couplings. We show that $t\bar th$ and Higgs property measurements at the High Luminosity LHC can constrain the ${\rm Re}\,ρ_{tt}$--${\rm Im}\,ρ_{tt}$ parameter space that could drive electroweak baryogenesis, but the $Γ_h$ width measurement must be considerably improved beyond current projections.

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Wei-Shu Hou, Masaya Kohda, Tanmoy Modak. 2018-10-14. Probing for Extra Top Yukawa Couplings in Light of $t\bar th(125)$ Observation. https://doi.org/10.1103/physrevd.98.075007

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