Cooling and noise performance of the ATLAS ITk strip system tests

The current tracking system of the ATLAS detector will be replaced by the new Inner Tracker (ITk) to cope with the challenging conditions expected at the High Luminosity Large Hadron Collider. This new tracking system will be an all-silicon detector consisting of silicon pixel sensors in the inner most layers and silicon micro-strips sensors in the outer layers. A central barrel section surrounds the interaction point and two end-cap sections cover the forward regions. This contribution focuses on the results of the system tests for the ITk strips detector in which several close-to-final detector components are evaluated before production. The barrel system tests structure at CERN consists of up to eight staves, while for the end-caps a structure at DESY is loaded with up to twelve petals. Staves (petals) consist of core structures loaded with square (trapezoid) shaped sensors of various lengths and strip pitches, and include readout and power electronics mounted on top of the sensors. Objects are mechanically held in place in a support structure and connected to the electrical, optical and cooling services as true as possible to the final system. With these setups, it is possible to validate the detector design, including the verification of the detector data acquisition, powering and cooling. This article gives an overview of the system tests and summarizes their current status by showing a selection of test results.