Abstract: The result of a search for flavor changing neutral currents (FCNC) through single top quark production in association with a photon is presented. The study is based on proton-proton collisions at a center-of-mass energy of 8 TeV using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.8 fb?1. The search for t? events where t ? Wb and W ? ?? is conducted in final states with a muon, a photon, at least one hadronic jet with at most one being consistent with originating from a bottom quark, and missing transverse momentum. No evidence of single top quark production in association with a photon through a FCNC is observed. Upper limits at the 95% confidence level are set on the tu? and tc? anomalous couplings and translated into upper limits on the branching fraction of the FCNC top quark decays: ?(t ? u?) < 1.3 × 10? 4 and ?(t ? c?) < 1.7 × 10? 3. Upper limits are also set on the cross section of associated t? production in a restricted phase-space region. These are the most stringent limits currently available.

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