%0 Journal Article %T Search for direct top squark pair production in events with a Z boson, b-jets and missing transverse momentum in root s=8 TeV pp collisions with the ATLAS detector %A ATLAS Collaboration (Aad, G. et al %A Cabrera Urban, S. %A Castillo Gimenez, V. %A Costa, M. J. %A Fassi, F. %A Ferrer, A. %A Fiorini, L. %A Fuster, J. %A Garcia, C. %A Garcia Navarro, J. E. %A Gonzalez de la Hoz, S. %A Hernandez Jimenez, Y. %A Higon-Rodriguez, E. %A Irles Quiles, A. %A Kaci, M. %A King, M. %A Lacasta, C. %A Lacuesta, V. R. %A March, L. %A Marti-Garcia, S. %A Miñano, M. %A Mitsou, V. A. %A Moles-Valls, R. %A Oliver Garcia, E. %A Pedraza Lopez, S. %A Perez Garcia-Estañ, M. T. %A Romero Adam, E. %A Ros, E. %A Salt, J. %A Sanchez Martinez, V. %A Soldevila, U. %A Sanchez, J. %A Torro Pastor, E. %A Valero, A. %A Valladolid Gallego, E. %A Valls Ferrer, J. A. %A Villaplana Perez, M. %A Vos, M. %J European Physical Journal C %D 2014 %V 74 %N 6 %I Springer %@ 1434-6044 %G English %F ATLASCollaborationAad_etal2014 %O WOS:000337043800001 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=1823), last updated on Sat, 14 Feb 2015 14:35:31 +0000 %X A search is presented for direct top squark pair production using events with at least two leptons including a same-flavour opposite-sign pair with invariant mass consistent with the boson mass, jets tagged as originating from -quarks and missing transverse momentum. The analysis is performed with proton-proton collision data at collected with the ATLAS detector at the LHC in 2012 corresponding to an integrated luminosity of 20.3 fb. No excess beyond the Standard Model expectation is observed. Interpretations of the results are provided in models based on the direct pair production of the heavier top squark state () followed by the decay to the lighter top squark state () via , and for pair production in natural gauge-mediated supersymmetry breaking scenarios where the neutralino () is the next-to-lightest supersymmetric particle and decays producing a boson and a gravitino () via the process. %R 10.1140/epjc/s10052-014-2883-6 %U http://arxiv.org/abs/1403.5222 %U https://doi.org/10.1140/epjc/s10052-014-2883-6 %P 2883 - 25pp