Triggering on heavy ions at the ATLAS experiment

The ATLAS detector is designed for proton-proton collisions, potentially interesting events are selected by a three-level trigger system. We present simulations of ATLAS trigger system response during the Pb+Pb collisions. First, we briefly describe ATLAS trigger system and triggering strategy. Then we concentrate mainly on the calorimeter triggering at the first level and we propose small changes to the default trigger strategy to meet specific requests of the heavy ion collisions.