Development and Calibration of a Dynamic Gas Supply System for Straw Detector Applications

Straw tube detectors are widely employed in cosmic ray and high-energy physics experiments for their high spatial and temporal resolution. The stability and precision of their operation strongly depend on the composition of the working gas mixture. This work presents the development and calibration of a dynamic gas supply system designed for use with straw detectors. The system integrates RRG-12 and RRG-15 mass flow controllers regulated via a KGS-3 control unit, enabling real-time mixing and flow control of Ar/CO₂ mixtures. Flow calibration using the volumetric water displacement method confirmed a linear correlation between controller settings and actual flow rates, with deviations below 6%. Additionally, spectral calibration was carried out using an Fe-55 radioactive source to fine-tune gas composition by comparing the ionization response with that of a reference gas mixture. The results demonstrate that the system provides accurate, stable, and reproducible gas delivery suitable for both laboratory use and large-scale experimental setups involving straw detectors. Future applications include muon track reconstruction using the developed gas system.