| The Standard Model(SM)of particle physics is a quantum field theory that describes the known fundamental particles and their interactions.SM predicts the existence of three generations of fermions,which has been confirmed by experiments.But why are there only three generations?So far,we have no good explanation,so it is worth exploring the experimental results of other fermions.In a new class of particles there are nonchiral? color singlet fermions that couple to SM leptons,this class of particles are referred to as vector-like leptons(VLLs),which have been widely concerned in experiment and theories.In this paper,we consider SU(2)L-singlet charged vector-like lepton(VLL)model,which is among the simplest viable SM extensions near the electroweak scale.VLLs(?'±)are hypothetical new fermions that transform in non-chiral representations of the unbroken SM gauge group.VLLs and their associated SM leptons have identical lepton numbers.The existing literature shows that the singlet VLLs suffer from a big difficult challenge for discovery at future proton-proton colliders.In the singlet VLL model,we study the prospects of searching for the VLLs in pure leptonic,fully hadronic and semileptonic channels at e+e-colliders.We perform a detailed detector simulation of the signal and backgrounds and display the excluding and discovering capability at different colliders.We find that there is an opportunity for excluding the region m?'±?[180GeV,240GeV]with L?[3.0fb-1,14.9fb-1]([0.1fb-1,0.3fb-1])at ILC of(?)GeV,the region m?'±?[240GeV,450GeV]with L?[9.9fb-1,23.1fb-1]([0.2fb-1,0.3fb-1])at ILC of(?)GeV and the region m?'±?[450GeV,700GeV]with L ?[52.1fb-1,197.9fb-1]([2.21fb-1,4.5fb-1])at CLIC of(?)GeV in the pure leptonic(fully hadronic)channel.It is more optimistic for excluding and discovering the singlet VLL through the fully hadronic channel at future high energy e+e-colliders,and searching the singlet VLL in e+e-collisions would greatly extend the search of future hadron colliders. |
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