![HEP2026: 42nd Conference on Recent Developments in High Energy Physics and Cosmology [NTUA] Jul 8 – 11, 2026](/event/1654737/logo-1929213524.png){kind=logo}
Speaker
Description
As part of the preparations for the High-Luminosity Large Hadron Collider (HL-LHC), the ATLAS experiment is undergoing major detector upgrades to cope with the significantly increased collision rates and data volumes expected during future operation. One of the most important upgrades is the replacement of the current Inner Detector with the new all-silicon Inner Tracker (ITk), designed to operate under the much harsher radiation and occupancy conditions of the HL-LHC.
During the integration and testing phases of the ITk Barrel, maintaining stable environmental conditions is essential to prevent condensation and ensure the safe operation of detector components. To support these activities, an Environmental Safety System (ESS) was developed for the ITk Barrel in the SR1 integration facility at CERN. The system is based on a Vaisala Indigo 520 transmitter coupled to two DMP8 dew-point probes installed on opposite sides of the detector volume. It continuously monitors dew point, temperature, and relative humidity, while dedicated relay outputs provide robust safety interlocks to the cooling plant.
Monitoring, alarm handling, and data archiving are implemented through a WinCC OA application using Modbus TCP/IP communication. To validate the system performance and determine the lowest achievable dew point inside the detector volume, the barrel was flushed with dry air while environmental parameters were continuously recorded. Long-term operation of the setup also enabled the identification and mitigation of effects that could potentially lead to spurious cooling interlocks.
The ESS has subsequently been integrated into the Integration Finite State Machine (FSM) of the ITk Strip Barrel Detector Control System (DCS), providing environmental supervision and safety functionality during detector testing and commissioning. Additionally, a dedicated setup was developed to measure the gas leak rate of the Barrel Outer Cylinder, providing valuable input for the assessment of the detector's environmental integrity and long-term operational stability.
The developed ESS and gas-leak measurements systems constitute key elements of the ITk Strip Barrel integration infrastructure, providing reliable detector protection, continuous environmental supervision, and valuable operational feedback during the detector integration, validation, and commissioning phases at CERN. The design, implementation, commissioning, and operational experience of these systems, as well as their contribution to the safe integration and testing of the ITk Strip Barrel at CERN, will be presented.