Exclusive window onto Higgs Yukawa couplings

Area of Science:

• Particle Physics
• Higgs Boson Physics
• Quantum Chromodynamics

Background:

• The Standard Model describes fundamental particles and forces, but the Higgs boson's interactions with lighter quarks are not precisely known.
• Yukawa couplings govern the interaction strength between the Higgs boson and fermions, including quarks.
• Flavor-conserving and flavor-violating couplings to first- and second-generation quarks are particularly challenging to measure.

Purpose of the Study:

• To investigate the potential of rare Higgs boson decays (h→MV) for probing Higgs-quark Yukawa couplings.
• To calculate branching ratios for these rare decays within the Standard Model and its extensions.
• To assess the experimental feasibility of observing these processes at current and future colliders.

Main Methods:

• Theoretical calculation of branching ratios for Higgs decays into vector mesons (M) and photons (γ), W bosons, or Z bosons (V).
• Analysis of both flavor-conserving and flavor-violating Higgs-quark interactions.
• Evaluation of experimental signatures and sensitivities at high-luminosity hadron colliders.

Main Results:

• Rare Higgs decays h→MV provide a novel probe for both flavor-conserving and flavor-violating Higgs-quark Yukawa couplings.
• Branching ratios for these rare decays are calculated, offering quantitative predictions.
• The study highlights the unique sensitivity of high-luminosity LHC and future colliders to these couplings.

Conclusions:

• Measuring rare Higgs decays h→MV is a promising avenue for precisely determining Higgs boson interactions with light quarks.
• These measurements offer a unique window into fundamental physics beyond the Standard Model.
• The proposed measurements provide strong motivation for the development of high-luminosity and future hadron collider facilities.