Search for gluino-mediated scalar top and bottom quark production in final states with missing transverse energy and at least three $b$-jets with the ATLAS Detector.

The results of a search for gluino-mediated pair production of the scalar partners of the top and bottom quarks in 4.7 fb-1of pp collisions at sqrt(s)=7 TeV using the ATLAS detector are reported. A search for scalar top and bottom quarks is performed in events with large missing transverse momentum and 4 or 6 jets in the final state of which at least 3 are identified as originating from a b-quark. Gluino masses up to 1 TeV are excluded, depending on the model considered.