Search for single top-quark production via flavour changing neutral currents at 8 TeV with the ATLAS detector

A search for single top-quark production via flavour changing neutral current processes from gluon plus up- or charm--quark initial states in proton--proton collisions at the LHC is presented. Data collected with the ATLAS detector in 2012 at a centre-of-mass energy of $8\;\mbox{TeV}$ and corresponding to an integrated luminosity of $20.3\;\mbox{fb}^{-1}$ are used. Candidate events for a top quark decaying into a lepton, a neutrino and a jet are selected and classified into signal- and background-like candidates using a neural network. No signal is observed and an upper limit on the production cross-section multiplied by the $t \rightarrow Wb$ branching fraction is set. The observed $95\,\%$ CL limit is $\sigma_{qg \rightarrow t} \times B(t \rightarrow Wb)Wb)