Searching for a flavor changing decay t ⟶ c h at the LHC

by Dr Masaya Khoda (National Taiwan University)

Tuesday Aug 27, 2013, 3:00 PM → 4:00 PM Asia/Seoul

201-4호 (제1과학관)

Since the landmark discovery of a 126 GeV boson in 2012 at the LHC, a lot of efforts have been paid to address the question of whether it is the genuine Higgs boson of the standard model or not. In this talk I will discuss about a flavor changing neutral Higgs coupling with top and charm quarks based on a two Higgs doublet model with general Yukawa structure. Identifying the 126 GeV boson as a lighter CP-even Higgs boson h, such a tch coupling can induce a flavor changing top decay t -> ch, which is highly suppressed in the standard model, therefore, should reveal a non-standard nature of the Higgs boson, if observed at the LHC. With abundant top-anti-top pairs produced at the LHC, t -> ch can induce extra Higgs production events with accompanying cbW activity, in addition to the standard Higgs production mechanisms. I will show existing h -> ZZ^* data can already probe t -> ch branching ratio at 1% level. I will also discuss about flavor physics with a large tch coupling, which also affects charged Higgs couplings to quarks.