Overview of the ATLAS detector at LHC

ATLAS is a general-purpose experiment that will exploit the full potential of the LHC p-p collision program. The design aspects of the ATLAS sub-detectors are described here, including performance results from the prototypes being built in the past years. Most of the information is taken from the recently published technical design reports for all the sub-systems of the experiment. In addition, some highlights of the LHC machine and its challenges are described in the beginning. (9 refs).