# Search for flavour-changing neutral current top-quark decays to qZ in pp collision data collected with the ATLAS detector at s√=8 TeV

 Title: Search for flavour-changing neutral current top-quark decays to qZ in pp collision data collected with the ATLAS detector at s√=8 TeV Author: Clark, Brian Lee; Franklin, Melissa; Huth, John; Ippolito, Valerio; Lazovich, Tomo; Lopez Mateos, David; Mercurio, Kevin ; Morii, Masahiro; Spearman, William; Sun, Siyuan; Tolley, Emma; Tuna, Alexander; Yen, Andy; Zambito, Stefano Note: Order does not necessarily reflect citation order of authors. Citation: ATLAS Collaboration. 2016. “Search for flavour-changing neutral current top-quark decays to qZ in pp collision data collected with the ATLAS detector at s√=8 TeV.” The European Physical Journal C 76 (1) (January). doi:10.1140/epjc/s10052-015-3851-5. Full Text & Related Files: 10.1140%2Fepjc%2Fs10052-015-3851-5.pdf (2.116Mb; PDF) Abstract: A search for the flavour-changing neutral-current decay t→qZ is presented. Data collected by the ATLAS detector during 2012 from proton-proton collisions at the Large Hadron Collider at a centre-of-mass energy of s√=8 TeV, corresponding to an integrated luminosity of 20.3 fb−1, are analysed. Top-quark pair-production events with one top quark decaying through the t→qZ (q=u,c) channel and the other through the dominant Standard Model mode t→bW are considered as signal. Only the decays of the Z boson to charged leptons and leptonic W boson decays are used. No evidence for a signal is found and an observed (expected) upper limit on the t→qZ branching ratio of 7×10−4 (8×10−4) is set at the 95% confidence level. Published Version: doi:10.1140/epjc/s10052-015-3851-5 Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:33470145 Downloads of this work: