Data driven background determination for SUSY searches with ATLAS

Supersymmetry (SUSY) is an attractive extension of the Standard Model possibly solving many standing issues in particle physics and cosmology. The general purpose ATLAS detector at the Large Hadron Collider (LHC) is an experiment capable of discovering or excluding TeV SUSY. However discovery can only be claimed when the Standard Model backgrounds are understood and are under control. The expectations at the LHC are that Monte Carlo simulation predictions will not be sufficient to achieve this, the backgrounds will have to determined from data itself. In this note we will highlight some data driven methods developed to estimate backgrounds and measure a possible SUSY excess.