Speaker
Giuseppe Fasanella
(Universite Libre de Bruxelles (BE))
Description
The recent discovery of a Higgs boson at the LHC sets strong constraints
on a simple, sequential third generation of quarks. Still, the presence
of new physics is necessary to stabilize the mass of the Higgs boson, if
one wants to avoid an unnaturally high level of fine tuning of the theory.
In supersymmetry, bosonic top quark partners would cancel the loops that
induce this large instability. Similarly, fermionic top quark partner quarks
can also serve this purpose. We present a search for a new T particle, which
is a vector-like partner of the top quark, focusing on the T quark pair
production. We use data collected with the CMS experiment during the year
2012, in proton-proton collisions at the LHC at a centre-of-mass energy of
8 TeV. Older searches for heavy vector-like-quarks focused separately either
on the T → bW or T → tZ final states. The precise knowledge of the Higgs
boson mass now allows to target the T → tH decay as well. Here we focus
exclusively on events with at least one top partner undergoing the T → tH
decay chain; in order to ensure a Higgs boson is actually present in the
final state, we exploit the Higgs to diphoton final state.
Author
Giuseppe Fasanella
(Universite Libre de Bruxelles (BE))
