Squark flavour violation and naturalness at the LHC

While rare meson decays place stringent constraints on much of the flavour violating parameter space of supersymmetric models, the mixing between right-handed top and charm squarks is so far unconstrained by the available data. Such mixing has in fact a very appealing phenomenology: it significantly weakens the current experimental bounds from direct squark searches and leads to a modest reduction of fine-tuning. The scenario can be tested already with the present 8 TeV data set by looking for the flavour violating final state t anti-t + missing E_T, thanks to the large squark pair production cross section.