Speaker
Javier Montejo Berlingen
(IFAE - Barcelona (ES))
Description
Since the discovery of a Higgs-‐like boson by the ATLAS and CMS experiments at the LHC, the emphasis has shifted towards measurements of its properties in order to determine whether the new particle is the Standard Model (SM) Higgs boson, or something else. Of particular importance is top-‐Higgs Yukawa coupling which, due to the large top quark mass, is close to unity, making the top quark the most strongly-‐coupled SM particle to the electroweak symmetry breaking sector and responsible for the instability of the Higgs boson mass against radiative corrections and motivates physics beyond the SM. The top-‐Higgs Yukawa coupling can be measured by identifying events with a Higgs boson is produced in association with a ttbar pair (ttH). This poster presents the latest results on the search for ttH production by the ATLAS experiment using the H-‐>bb-‐bar decay mode, which has a large branching ratio and allows the kinematic reconstruction of the Higgs boson. This results in spectacular final state signatures involving one or two isolated leptons (electron or muon), high transverse missing energy, and at least four b-‐tagged jets. However, this measurement is very challenging due to the large physics background from ttbar+jets, affected by large systematic uncertainties, and large combinatorial backgrounds.
Author
Javier Montejo Berlingen
(IFAE - Barcelona (ES))
