@article{cee39642f8a74ccda8bc0d202b20bf94,
title = "Search for direct top squark pair production in events with a Z boson, b-jets and missing transverse momentum in √s = 8 TeV pp collisions with the ATLAS detector",
abstract = "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 Z boson mass, jets tagged as originating from b-quarks and missing transverse momentum. The analysis is performed with proton–proton collision data at √s = 8 TeV collected with the ATLAS detector at the LHC in 2012 corresponding to an integrated luminosity of 20.3 fb−1. 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 (t2) followed by the decay to the lighter top squark state (t1) via t2 → Zt1, and for t1 pair production in natural gaugemediated supersymmetry breaking scenarios where the neutralino (χ 01) is the next-to-lightest supersymmetric particle and decays producing a Z boson and a gravitino (G ) via the χ 01 → Z G process.",
author = "{The ATLAS Collaboration} and G. Aad and B. Abbott and J. Abdallah and Khalek, {S. Abdel} and O. Abdinov and R. Aben and B. Abi and M. Abolins and Zeid, {O. S.Abou} and H. Abramowicz and H. Abreu and R. Abreu and Y. Abulaiti and Acharya, {B. S.} and L. Adamczyk and Adams, {D. L.} and J. Adelman and S. Adomeit and T. Adye and T. Agatonovic-Jovin and Aguilar-Saavedra, {J. A.} and M. Agustoni and Ahlen, {S. P.} and A. Ahmad and F. Ahmadov and G. Aielli and {\AA}kesson, {T. P.A.} and G. Akimoto and Akimov, {A. V.} and Alberghi, {G. L.} and J. Albert and S. Albrand and Verzini, {M. J.Alconada} and M. Aleksa and Aleksandrov, {I. N.} and C. Alexa and G. Alexander and G. Alexandre and T. Alexopoulos and M. Alhroob and G. Alimonti and L. Alio and J. Alison and Allbrooke, {B. M.M.} and Allison, {L. J.} and Allport, {P. P.} and Allwood-Spiers, {S. E.} and N. Kimura and T. Mitani and K. Yorita",
note = "Funding Information: We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWF and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT and NSRF, Greece; ISF, MINERVA, GIF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT, Portugal; MNE/IFA, Romania; MES of Russia and ROSATOM, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MIZ{\v S}, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Leverhulme Trust, UK; DOE and NSF, USA. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN and the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL (USA) and in the Tier-2 facilities worldwide. Publisher Copyright: {\textcopyright} 2014, CERN for the benefit of the ATLAS collaboration 2014.",
year = "2014",
month = jun,
day = "3",
doi = "10.1140/epjc/s10052-014-2883-6",
language = "English",
volume = "74",
journal = "European Physical Journal C",
issn = "1434-6044",
publisher = "Springer New York",
number = "6",
}