Single Event Upset Studies Using the ATLAS SCT

Single Event Upsets (SEU) are expected to occur during high luminosity running of the ATLAS SemiConductor Tracker (SCT). The SEU cross sections were measured in pion beams with momenta in the range 200 to 465 MeV/c and proton test beams at 24 GeV/c but the extrapolation to LHC conditions is non-trivial because of the range of particle types and momenta. The SEUs studied occur in the \emph{p-i-n} photodiode and the registers in the ABCD chip. Comparisons between predicted SEU rates and those measured from ATLAS data are presented. The implications for ATLAS operation are discussed.