Search for δ±± with new decay patterns at the LHC SEARCH for δ±± with NEW DECAY PATTERNS ... CHUAN-HUNG CHEN and TAKAAKI NOMURA

A search for the doubly charged Higgs (δ±±) is performed in the two-Higgs-doublet extension of the conventional type-II seesaw model. We find that a fantastic mixing effect between the singly charged Higgses of the Higgs doublet and triplet arises from the scalar potential. The mixing leads to the following intriguing phenomena: (i) the mass splittings in triplet particles are magnified; (ii) QCD processes dominate the production of δ±±; and (iii) the new predominant decay channels of δ±± are δ±±→W±[∗]H1(2)±(∗), but not δ±→(-±-±,W±W±), which are usually discussed in the literature. With a luminosity of 40fb-1 and collision energy of 13 TeV, we demonstrate that a δ±± with mass below 330 GeV could be observed at the 5σ level. Moreover, when the luminosity approaches 300fb-1, the observed mass of δ±± could reach up to 450 GeV.