Experimental Studies of Ion Backflow for a Bulk Micromegas Detector Using Various Argon-Based Gas Mixtures

International audienceTheRout, Prasant Kumar micropatternBhattacharya, Deb Sankar gaseousBhattacharya, Purba detectorsMukhopadhyay, Supratik (MPGD) areBhattacharya, Sudeb fastMajumdar, Nayana radiationSarkar, Sandip detectorsColas, Paul capableAttie, David ofGanjour, Serguei operatingBhattacharya, Aparajita in high-luminosity environment and offer high gain, good position and time resolutions. Avalanche-induced photons and ions lead to secondary effects that can limit the operation of gaseous ionization detectors. For example, ion backflow (IBF) makes a detector incapable in high-flux scenarios by distorting the electric field locally. In the present work, IBF has been measured using two drift meshes in the experimental set-up and several Ar-based gas mixtures, in particular, Argon + Isobutane (95:5), T2K gas composed of Argon + CF$_{4}$ + Isobutane (95:3:2) and Argon + CO$_{2}$ (80:20). We will present the effect of various experimental parameters on IBF and discuss optimization of the related experimental set-up