Speaker
Description
The Resistive Plate Chambers (RPC) of the CMS experiment operate with a gas mixture composed of 95.2% C₂H₂F₄, a greenhouse gas with high Global-Warming Potential (GWP). In recent years, several eco-friendly alternatives, such as hydrofluoroolefins (HFOs), have been investigated to identify sustainable replacements that preserve the detector performance. Another promising approach is to partially substitute C₂H₂F₄ with CO₂, potentially reducing the GWP of the mixture by 30–40%. These studies are being carried out at the CERN Gamma Irradiation Facility (GIF++), which replicates the conditions expected during the High-Luminosity Phase-2 data taking at the Large Hadron Collider (HL-LHC), using an 11.5 TBq gamma source and a muon beam. This contribution presents updated results on the performance of two 1.4 mm gap RPC chambers operating with various eco-gas and CO₂-based mixtures under high-rate gamma irradiation. In addition, it highlights the latest results in aging studies, providing a deeper insight into the long-term behavior and stability of these alternative gas mixtures for the future of the RPC.