Doubly Charged Lepton Search Potential of the FCC-Based Energy-Frontier Electron-Proton Colliders

TL;DR

This paper investigates the potential to discover doubly charged leptons at future FCC-based electron-proton colliders, providing mass limits based on collider energy and isospin multiplet assumptions.

Contribution

It introduces a detailed analysis of doubly charged lepton production at FCC colliders, including cross section calculations, kinematic cuts, and discovery potential for different isospin states.

Findings

Discovery mass limits reach up to 12.9 TeV at 3.46 TeV collider energy for I_W=1.

Discovery mass limits reach up to 20.0 TeV at 31.6 TeV collider energy for I_W=3/2.

Higher collider energies significantly extend the potential discovery mass range.

Abstract

We search for the doubly charged leptons ($L^{--}$) predicted in composite models including extended weak isospin multiplets namely, $I_{W}=1$ and $I_{W}=3/2$ at the Future Circular Collider (FCC)-based energy-frontier electron-proton colliders with the center-of-mass energies of $\sqrt{s}=3.46$ TeV, $\sqrt{s}=10$ TeV, and $\sqrt{s}=31.6$ TeV, respectively. We deal with the $e^{-}p\rightarrow L^{--}X\rightarrow e^{-}W^{-}X$ process, calculate the production cross sections and give the normalized transverse momentum and pseudorapiditiy distributions of final state electron to obtain the kinematical cuts for the discovery. We show the statistical significance ($SS$) of the expected signal yield as a function of doubly charged lepton mass ($SS-M_{L}$ plots) to attain the doubly charged lepton discovery mass limits both for the $I_{W}=1$ and $I_{W}=3/2$. It is obtained that discovery mass limits on the mass of doubly charged lepton for $I_{W}=1$ ($I_{W}=3/2$) are, $2.21\,(2.73)$ TeV, $5.46\,(8.47)$ TeV, and $12.9\,(20.0)$ TeV for $\sqrt{s}=3.46$ TeV, $\sqrt{s}=10$ TeV, and $\sqrt{s}=31.6$ TeV, respectively.