Measuring the Higgs boson self-coupling at the Large Hadron Collider

Area of Science:

• High Energy Physics
• Particle Physics
• Collider Physics

Background:

• The Standard Model (SM) of particle physics describes fundamental particles and forces.
• The Higgs boson is a key particle in the SM, responsible for mass.
• Understanding the Higgs boson self-coupling is crucial for testing the SM.

Purpose of the Study:

• To investigate the capability of the Large Hadron Collider (LHC) in determining the Higgs boson self-coupling (lambda).
• To analyze Higgs boson pair production and its decay to same-sign dileptons via W+/- bosons.
• To assess the validity of approximations, such as the large top quark mass limit, in differential distribution analyses.

Main Methods:

• Simulating inclusive Higgs boson pair production at the LHC.
• Analyzing the decay of Higgs boson pairs to same-sign dileptons through W+/- bosons.
• Utilizing differential distributions to probe the Higgs boson self-coupling, lambda.
• Considering the impact of the top quark mass on signal analysis.

Main Results:

• The large top quark mass limit is not a suitable approximation for signal analysis using differential distributions.
• It is feasible at the LHC with design luminosity to establish a non-zero Higgs boson self-coupling.
• The ratio lambda/lambda(SM) can be constrained to the range of 0-3.7 at a 95% confidence level for Higgs boson masses between 150-200 GeV.

Conclusions:

• The LHC has the potential to measure the Higgs boson self-coupling with high precision.
• The study provides a method to experimentally probe fundamental aspects of the Higgs sector.
• Precise measurements of Higgs boson self-coupling can reveal deviations from the Standard Model.