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arXiv · 0706.1732

GeV Seesaw, Accidentally Small Neutrino Masses, and Higgs Decays to Neutrinos

Andre de Gouvea
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Abstract

If the Standard Model particle content is extended by gauge singlet fermions (right-handed neutrinos), active neutrinos generically acquire (Majorana) masses, in agreement with our current understanding of the lepton sector. If the right-handed neutrino masses are of the same order as the electroweak symmetry breaking scale, it is usually expected that these will not mediate any experimentally observable effects. Here, I explore the fact that this is not necessarily the case. If neutrino masses are "accidentally small", active-sterile mixing angles can, according to current experimental bounds, be as large as several percent. If this is the case, I argue that the dominant decay mode of light (M_H less than 130 GeV) Higgs bosons could be into an active and a sterile neutrino. The sterile neutrino decays promptly into a charge lepton and an on- or off-shell W-boson, so that the dominant Higgs boson decay mode is H to leptons + jets + missing transverse energy.

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Andre de Gouvea. 2007-07-11. GeV Seesaw, Accidentally Small Neutrino Masses, and Higgs Decays to Neutrinos. https://arxiv.org/abs/0706.1732

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