The ITk Common Monitoring and Interlock System

For the upgrade of the Large Hadron Collider (LHC) to the High Luminosity Large Hadron Collider (HL-LHC) the ATLAS detector will install a new Inner Tracker (ITk), which is completely built by silicon detectors. The most inner part is composed by pixel detectors, the outer part by strip detector elements. All together ca. 28000 detector modules will be installed in the ITk volume. Although different technologies were chosen for the inner and outer part, both detectors share a lot of commonalities concerning their requirements. These are operation in the harsh radiation environment, the restricted space for services, and the high power density, which requires a high efficient cooling system. While the sub detectors have chosen different strategies to reduce their powering services, they share the same CO2 cooling system. The main risks for operation are heat ups and condensation, therefore a common detector control system is under development. It provides a detailed monitoring of the temperature, the radiation and the humidity in the tracker volume. Additionally an interlock system, a hardware based safety system, is designed to protect the sensitive detector elements against upcoming risks. Another constraint is that - once the detector is installed - its components are not accessible for several years or even for the lifetime of the detector. Thus the control system must be fault tolerant and provide very good remote diagnostics. The components of the ITk common monitoring and interlock system are presented.