Performance of the ATLAS Minimum Bias and Forward Detector Triggers in 2011 Heavy Ion Run

This note describes the performance of the ATLAS minimum bias and forward detector triggers during the 2011 LHC Heavy Ion run. The efficiency, purity, and rate of triggers using a wide variety of ATLAS subdetectors are presented. As an application, we show the luminosity stability measurements during LHC Heavy Ion fills using the number of events passing minimum bias triggers and compare the event counts in subranges of individual LHC fills.