Strong double higgs production at the LHC

The hierarchy problem and the electroweak data, together, provide a plausible motivation for considering a light Higgs emerging as a pseudo-Goldstone boson from a strongly-coupled sector. In that scenario, the rates for Higgs production and decay di ff er signi fi cantly from those in the Standard Model. However, one genuine strong coupling signature is the growth with energy of the scattering amplitudes among the Goldstone bosons, the longitudinally polarized vector bosons as well as the Higgs boson itself. The rate for double Higgs production in vector boson fusion is thus enhanced with respect to its negligible rate in the SM. We study that reaction in p p collisions, where the production of two Higgs bosons at high p T is associated with the emission of two forward jets. We concentrate on the decay mode hh -> W W-(()) WW(()) and study the semi-leptonic decay chains of the W's with 2, 3 or 4 leptons in the fi nal states. While the 3 lepton fi nal states are the most relevant and can lead to a 3 sigma signal signi fi cance with 300 fb(-1) collected at a 14TeV LHC, the two same-sign lepton fi nal states provide complementary information. We also comment on the prospects for improving the detectability of double Higgs production at the foreseen LHC energy and luminosity upgrades.

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Roberto Contino, Riccardo Rattazzi
2010
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https://infoscience.epfl.ch/record/152039?ln=fr

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