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LHC 750 GeV Diphoton excess in a radiative seesaw model

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 نشر من قبل Kenji Nishiwaki
 تاريخ النشر 2015
  مجال البحث
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We investigate a possibility for explaining the recently announced 750,GeV diphoton excess by the ATLAS and the CMS experiments at the CERN LHC in a model with multiple doubly charged particles, which was originally suggested for explaining tiny neutrino masses through a three-loop effect in a natural way. The enhanced radiatively generated effective coupling of a new singlet scalar $S$ with diphoton with multiple charged particles in the loop enlarges the production rate of $S$ in $ppto S+X$ via photon fusion process and also the decay width $Gamma(Sto gammagamma)$ even without assuming a tree level production mechanism. We provide detailed analysis on the cases with or without allowing the mixing between $S$ and the standard model Higgs doublet.



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