Studies of initial state gluon radiation in Drell-Yan events at the LHC

Initial State Radiation (ISR) primarily consists of gluons radiated before the hard interaction. The uncertainty in the model of ISR in the Monte Carlo simulation is a source of systematic uncertainty for many measurements at the LHC. In order to study ISR, Drell-Yan events are suitable because the Drell-Yan process has a leptonic final state that is not sensitive to final state gluon radiation. We present a method to determine systematic uncertainties due to ISR by comparison of Monte Carlo simulated Drell-Yan events to future data, expected from the initial run of the ATLAS experiment in 2010.