Testing CP-violation in a heavy Higgs sector at CLIC

Area of Science:

• High Energy Physics
• Particle Physics
• Beyond Standard Model Physics

Background:

• Extended Higgs models predict heavy Higgs states with potential CP-violating properties.
• Probing the CP nature of Higgs bosons is crucial for understanding fundamental physics.
• Existing methods may not fully distinguish between CP-even and CP-odd components of heavy Higgs states.

Purpose of the Study:

• To propose a novel method for probing CP-violation in the heavy (pseudo)scalar sector of an extended Higgs model.
• To simultaneously utilize Higgs-vector boson (HVV) and Higgs-top quark (Htt-bar) interactions of a heavy Higgs state (H).
• To confirm CP-violation by discovering both CP-even and CP-odd components of the heavy Higgs state.

Main Methods:

• Simultaneous use of HVV and Htt-bar interactions for a heavy Higgs state.
• Probing CP-even component via tree-level HVV interaction.
• Probing CP-odd component by analyzing the tt-bar pair as a 1S0 state.
• Exploiting Higgs production via vector-boson fusion (VBF) at the Compact Linear Collider (CLIC).
• Analyzing the azimuthal angle distribution of leptons from top and antitop quark decays.

Main Results:

• The proposed method allows for the simultaneous probing of CP-even and CP-odd components of a heavy Higgs state.
• CP-violation can be confirmed if both components are discovered.
• The Compact Linear Collider (CLIC) is identified as a suitable facility for this investigation.
• Analysis of azimuthal angle distributions effectively disentangles the CP nature of the heavy Higgs state.
• The method's implications for CP-violating two-Higgs-doublet models (2HDM) are demonstrated.

Conclusions:

• The proposed method provides a viable strategy to detect CP-violation in heavy Higgs sectors.
• Simultaneous observation of CP-even and CP-odd contributions is a key signature for CP-violation.
• The Compact Linear Collider (CLIC) offers the necessary environment and analysis tools to implement this method.
• This research contributes to a deeper understanding of Higgs physics beyond the Standard Model.