A search for excited leptons in pp collisions at root s=7 TeV

A search for excited leptons is carried out with the CMS detector at the LHC, using 36 pb(-1) of pp collision data recorded at root s = 7 TeV. The search is performed for associated production of a lepton and an oppositely charged excited lepton pp -> ll{*}, followed by the decay l{*} -> l gamma, resulting in the eey final state, where l = e, mu. No excess of events above the standard model expectation is observed. Interpreting the findings in the context of l{*} production through four-fermion contact interactions and subsequent decay via electroweak processes, first upper limits are reported for l{*} production at this collision energy. The exclusion region in the compositeness scale A and excited lepton mass M(l{*}) parameter space is extended beyond previously established limits. For Lambda = M(l{*}), excited lepton masses are excluded below 1070 GeV/c(2) for e{*} and 1090 GeV/c(2) for mu{*} at the 95% confidence level.