Probing Extra Dimensions through the Invisible Higgs Decay

In the large extra dimension model of Arkani-Hamed, Dimopoulos and Dvali the presence of an interaction between the Ricci scalar curvature and the Higgs doublet of the Standard Model makes a light Higgs boson observable at LHC at the 5 σ level through the fusion process pp → W ∗W ∗ +X → Higgs, graviscalars+X → invisible+X for the portion of the Higgs-graviscalar mixing (ξ) and effective Planck mass (MD) parameter space where channels relying on visible Higgs decays fail to achieve a 5 σ signal. However even if the LHC has a good chance of seeing a signal, it will not be able to determine the parameters of the model with any real precision. This goal can be reached by adding the following LC measurements: γ + E / T , Higgs production and decay in the visible SM-like final states and in the invisible final state.