Integration Tests with 2S Module Prototypes for the Phase-2 Upgrade of the CMS Outer Tracker

The CMS experiment will be upgraded by 2028 to fully exploit the physics potential from the increased luminosity of the HL-LHC. The entire tracking system will be replaced during this Phase-2 Upgrade. The CMS Outer Tracker will be equipped with modules containing two silicon sensors that are separated by a few mm to provide an on-module transverse momentum measurement. These are placed on mechanical structures called ladders in the central barrel of the Outer Tracker or discs in the endcap regions. During the prototyping phase the modules are initially investigated individually to evaluate their performance. Next steps towards the production phase are integration tests performed with the purpose to test the module functionality on the final detector structures. Investigations focus on the cooling performance as well as on electrical performance of a group of modules on the mechanical structures. This contribution summarizes integration tests with the Outer Tracker module prototypes. The main focus is on a thermal ladder integration test performed at CERN and a full ladder integration test at Institut Pluridisciplinaire Hubert Curien (IPHC, Strasbourg). A short summary of an integration test on endcap discs at DESY (Hamburg) is also given.