Same-Sign Tetralepton Signature at Large Hadron Collider, and future $pp$ Collider

TL;DR

This paper explores a distinctive same-sign tetra-lepton signal in the type II seesaw model, analyzing its potential observability at the High-Luminosity LHC and future 100 TeV colliders across various parameter ranges.

Contribution

It introduces the analysis of a novel same-sign tetra-lepton signature from neutral Higgs mixing in the type II seesaw model, considering realistic parameter spaces consistent with neutrino data and collider limits.

Findings

Doubly charged Higgs around 250 GeV can produce many events at HL-LHC.

At a 100 TeV collider, up to 1000 same-sign tetra-lepton events are possible.

Parameter regions with specific Higgs masses and triplet vev yield significant signals.

Abstract

We analyze a novel signature of the type II seesaw model - same-sign tetra-lepton signal arising from the mixing of neutral Higgs bosons and their subsequent decays to singly and doubly charged Higgs bosons. For this, we consider wide ranges of the triplet vacuum expectation value (vev) and Yukawa couplings, that are consistent with the observed neutrino masses and mixing as well as the LHC search limits. We find that a doubly charged Higgs boson with mass around 250 GeV and triplet vev around $10^{-4}-10^{-2}$ GeV can give significantly large number of events through it decay to same-sign $W$ gauge bosons at High-Luminosity LHC with $3000 \text{fb}^{-1}$ of data. We also pursue the analysis for a future hadron collider with the c.m. energy of 100 TeV. Considering a heavy Higgs boson around 900 GeV and an intermediate region of the triplet vev, where both same-sign dilepton and gauge boson decays can occur, we identify a limited range of the parameters where the number of same-sign tetra-lepton events are as large as 1000.