Buried Higgs boson

Physical review D: Particles and fields (Impact Factor: 4.86). 10/2009; 80(7). DOI: 10.1103/PHYSREVD.80.075008
Source: OAI


We present an extension of the MSSM where the dominant decay channel of the Higgs boson is a cascade decay into a four-gluon final state. In this model the Higgs is a pseudo-Goldstone boson of a broken global symmetry SU(3)-> SU(2). Both the global symmetry breaking and electroweak symmetry breaking are radiatively induced. The global symmetry breaking pattern also implies the existence of a light (few GeV) pseudo-Goldstone boson eta which is a singlet under the standard model gauge group. The h -> eta eta branching fraction is large, and typically dominates over the standard h -> b b decay. The dominant decay of eta is into two gluons, while the decays to photons, taus or lighter standard model flavors are suppressed at the level of 10^(-4) or more. With h-> 4 jets as the dominant decay, the Higgs could be as light as 78 GeV without being detected at LEP, while detection at the LHC is extremely challenging. However many of the super- and global symmetry partners of the standard model particles should be easily observable at the LHC. Furthermore, the LHC should be able to observe a "wrong Higgs" that is a 300-400 GeV heavy Higgs-like particle with suppressed couplings to W and Z that by itself does not account for electroweak precision observables and the unitarity of WW scattering. At the same time, the true Higgs is deeply buried in the QCD background.

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Available from: Brando Bellazzini, Dec 22, 2014
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