Abstract
A search is presented for heavy-quark pair production (QQ_) under the decay hypothesis Q___W+qW-__ with q=d, s, b for up-type Q or q=u, c for down-type Q. The search is performed with 1.04fb-1 of integrated luminosity from pp collisions at ís=7TeV collected by the ATLAS detector at the CERN LHC. Dilepton final states are selected, requiring large missing transverse momentum and at least two jets. Mass reconstruction of heavy-quark candidates is performed by assuming that the W boson decay products are nearly collinear. The data are in agreement with standard model expectations; a heavy quark with mass less than 350 GeV is excluded at 95% confidence level. © 2012 CERN. Published by the American Physical Society under the terms of the http://creativecommons.org/licenses/by/ 3.0/ Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.