Search for Physics Beyond the Standard Model in Multi-jet Events Recorded with the ATLAS Detector in p-p collisions at center of Mass Energy = 8 TeV using the Large Hadron Collider

A search for physics beyond the Standard Model with multi-jet signatures is presented using 20.3 inverse fb of proton-proton collision data recorded using the ATLAS detector at the Large Hadron Collider at a center-of-mass energy of 8 TeV. An original fit and extrapolation technique is used to estimate the QCD multi-jet background. No statistically significant deviations from Standard Model predic- tions are observed. The results are interpreted in terms of model-independent lim- its on the fiducial production cross section of multi-jet events and model-dependent limits in the context of TeV-scale gravity. The fiducial limits at 95% confidence level on multi-jet production are as low as 0.16 fb and the exclusion power in threshold mass for black hole and string ball production varies from 4.6 to 6.2 TeV for par- ticular models. These results are amongst the most stringent limits on TeV-scale gravity to date.