Event Details

Study of ttH and tH production in the multilepton channel at CMS

  • 2023-07-26

The discovery of the Higgs boson by the CMS and the ATLAS experiments opened a new era in experimental high-energy particle physics. It emphasizes the importance of determining the properties of the Higgs boson, particularly the trilinear Higgs self-coupling ($\lambda_{3}$). While the production of di-Higgs bosons provides direct information on $\lambda_{3}$, its cross-section is significantly lower than that of single Higgs production. Therefore, there is an alternative approach: examining deviations in $\lambda_{3}$ through precise measurements of single Higgs production processes, specifically focusing on the ttH production mode. The ttH production mode is considered a promising avenue because any modification to $\lambda_{3}$ would result in extreme deviations in the kinematic distributions of the Higgs boson in this channel. Additionally, the passage highlights the importance of studying the Yukawa coupling of the Higgs boson to the top quark. In the Standard Model (SM), this coupling is proportional to the fermion masses. By investigating top quark-associated Higgs boson production, one can directly probe the top-Higgs Yukawa coupling, which may be influenced by physics beyond the Standard Model.

It is already acknowledged that previous measurements of the Higgs coupling to the top, bottom quarks, and tau lepton are consistent with SM predictions within an uncertainty of about 10-15%. However, with the anticipated increase in production cross-sections and integrated luminosity in future experiments, such as the Run III and High Luminosity (HL) option, more accurate measurements of the Higgs boson couplings to other particles will be possible. This improved precision will further enhance our understanding of the top-Higgs coupling through ttH production, aiding in the exploration of new physics beyond the Standard Model.

The seminar will focus on the analysis of ttH + tH production inclusive cross-section measurements in the multilepton final state from the CMS collaboration. The description of the plan as well as an overview of the analysis strategy employed to obtain the results will be presented at this seminar.

PhD Scholar, Department of Physics, IIT Madras