Pair production of the fourth family charged sleptons at e+e- colliders

We study the pair production of (l) over bar (4), which is the supersymmetric partner of the fourth family charged lepton, at the e(+)e(-) colliders. It is shown that the investigation of this process at ILC/CLIC will give the opportunity to differentiate the MSSM with three and four families. The ILC with root s = 1TeV and L-int = 1 ab(-1) has the potential for the observation of the fourth family slepton with mass up to 420 GeV, if the fourth SM family neutrino has a Dirac nature. The CLIC with root s = 3TeV and L-int = 1 ab(-1) will enlarge the observation region up to m((l) over bar4) = 580 GeV. Copyright (C) EPLA, 2011