Search for New Phenomena in Monojet plus Missing Transverse Momentum Final States using 10fb-1 of pp Collisions at sqrt{s}=8 TeV with the ATLAS detector at the LHC

We report preliminary results on a search for new phenomena in monojet plus large missing transverse momentum final states. The analysis uses 10.5fb-1 of sqrt{s}=8TeV data collected in 2012 with the ATLAS detector. Good agreement is observed between the number of events in data and the Standard Model predictions. The results are translated into new limits on the production of light grativinos in association with gluinos or scalar quarks in a gauge-mediated supersymmetric model, leading to the best lower bound to date on the gravitino mass. Exclusion limits on models with large extra spatial dimensions and on pair production of weakly interacting dark matter candidates are also presented.