Determining the Higgs boson self coupling at hadron colliders

Inclusive Standard Model Higgs boson pair production at hadron colliders has the capability to determine the Higgs boson self-coupling, λ. We present a detailed analysis of the gg → HH → (W+W-)(W+W-) → (jjl±ν)(jjl'±ν) and gg→ HH → (W+W-)(W+W-) → (jjl±ν)(l'±νl''-+ν) (l, l', l'' = e, μ) signal channels, and the relevant background processes, for the CERN Large Hadron Collider, and a future Very Large Hadron Collider operating at a center-of-mass energy of 200 TeV. We also derive quantitative sensitivity limits for λ. We find that it should be possible at the LHC with design luminosity to establish that the Standard Model Higgs boson has a non-zero self-coupling and that λ/λSM can be restricted to a range of 0 - 3.8 at 95% confidence level (CL) if its mass is between 150 and 200 GeV. At a 200 TeV collider with an integrated luminosity of 300 fb-1, λ can be determined with an accuracy of 8 - 25% at 95% CL in the same mass range. (orig.)