Aad, G.G.AadAbajyan, T.T.AbajyanAbbott, B.B.AbbottAbdallah, J.J.AbdallahAbdel Khalek, S.S.Abdel KhalekAbdelalim, A.A.A.A.AbdelalimAbdinov, O.O.AbdinovAben, R.R.AbenAbi, B.B.AbiAbolins, M.M.AbolinsZwalinski, L.L.Zwalinski2019-07-092019-07-092013https://resolver.sub.uni-goettingen.de/purl?gro-2/58181We present a search for a light (mass < 2 GeV) boson predicted by Hidden Valley supersymmetric models that decays into a final state consisting of collimated muons or electrons, denoted “lepton-jets”. The analysis uses 5 fb−1 of √ s = 7 TeV proton–proton collision data recorded by the ATLAS detector at the Large Hadron Collider to search for the following signatures: single lepton-jets with at least four muons; pairs of lepton-jets, each with two or more muons; and pairs of lepton-jets with two or more electrons. This study finds no statistically significant deviation from the Standard Model prediction and places 95% confidence-level exclusion limits on the production cross section times branching ratio of light bosons for several parameter sets of a Hidden Valley model.19enCC BY 3.0530journal_article10.1016/j.physletb.2013.01.034598869https://resolver.sub.uni-goettingen.de/purl?gs-1/11038openAccess