PT Journal AU ATLAS Collaboration (Aad, Gea Alvarez Piqueras, D Cabrera Urban, S Castillo Gimenez, V Costa, MJ Fernandez Martinez, P Ferrer, A Fiorini, L Fuster, J Garcia, C Garcia Navarro, JE Gonzalez de la Hoz, S Hernandez Jimenez, Y Higon-Rodriguez, E Irles Quiles, A Jimenez Pena, J Kaci, M King, M Lacasta, C Lacuesta, VR Marti-Garcia, S Mitsou, VA Oliver Garcia, E Pedraza Lopez, S Perez Garcia-Estañ, MT Romero Adam, E Ros, E Salt, J Sanchez Martinez, V Soldevila, U Sanchez, J Valero, A Valladolid Gallego, E Valls Ferrer, JA Vos, M TI A search for prompt lepton-jets in pp collisions at root s=8 TeV with the ATLAS detector SO Journal of High Energy Physics JI J. High Energy Phys. PY 2016 BP 062 EP 51pp VL 02 IS 2 DI 10.1007/JHEP02(2016)062 LA English DE Hadron-Hadron scattering AB A search is presented for a new, light boson with a mass of about 1 GeV and decaying promptly to jets of collimated electrons and/or muons (lepton-jets). The analysis is performed with 20.3 fb(-1) of data collected by the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a centre-of-mass energy of 8 TeV. Events are required to contain at least two lepton-jets. This study finds no statistically significant deviation from predictions of the Standard Model and places 95% confidence-level upper limits on the contribution of new phenomena beyond the SM, incuding SUSY-portal and Higgs-portal models, on the number of events with lepton-jets. ER