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

Abstract

We search for the doubly charged leptons (L−−) predicted in composite models including extended weak isospin multiplets, namely, IW=1 and IW=3/2, at the Future Circular Collider- (FCC-) based energy-frontier electron-proton colliders with the center-of-mass energies of s=3.46 TeV, s=10 TeV, and s=31.6 TeV, respectively. We deal with the e−p⟶L−−X⟶e−W−X process, calculate the production cross sections, and give the normalized transverse momentum and pseudorapidity 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−ML plots) to attain the doubly charged lepton discovery mass limits for both the IW=1 and IW=3/2. It is obtained that discovery mass limits on the mass of doubly charged lepton for IW=1 (IW=3/2) are 2.21 2.73 TeV, 5.46 8.47 TeV, and 12.9 20.0 TeV for s=3.46 TeV, s=10 TeV, and s=31.6 TeV, respectively.

Perturbative unitarity bounds for fermions composite models

“…Here, L T = (ν L , L ) is the ordinary lepton doublet, g and g are the SU(2) L and U(1) Y gauge couplings and W W W µν , B µν are the field strength tensor of the corresponding gauge fields respectively; τ τ τ are the Pauli matrices and Y is the hypercharge, f and f are dimensionless couplings and are expected (and assumed) to be of order unity. Excited states interacting with the SM sector through the model Lagrangians (1.1)-(1.2) and (1.3) have been extensively searched for at high-energy collider facilities and their phenomenology has also been discussed in a series of recent papers [24,25,26,27,28,29,30,31,32,33]. The current strongest bounds are due to the recent LHC experiments.…”

Alternative signatures of the quintuplet fermions at the LHC and future linear colliders

“…Signatures of quintuplet fermions at LHC have been studied in detail in Ref: [33,34]. They are also a good candidate in Future collider experiments [35,36]. In these studies, the quintuplet decay directly into the Standard Model particles.…”

“…Cases studied so far include multilepton and multijet signatures both at the LHC [16,33] and the linear colliders [35,36,40]. In standard scenarios, the quintuplet decays directly into the SM particles.…”

A STUDY ON THE SEARCH POTENTIAL OF DOUBLY CHARGED LEPTONS AT THE SppC BASED ep COLLIDERS

“…), too [34][35][36][37][38][39][40][41][42][43][44]. In the literature there are phenomenological studies for the doubly charged leptons at the LHC [45][46][47][48][49][50][51][52][53][54], at the future   e e and e colliders [55][56][57][58], and at the future lepton-proton colliders [59][60][61]. The first limits for the mass of doubly charged leptons in ep collisions obtained as like that, for Lint >10 4 fb -1 , ML > 860 (1280) GeV at s =1.3 (1.98) TeV in [59].…”