Speaker
Description
The µRWELL detector, a novel Micro-Pattern Gaseous Detector (MPGD) technology, uses a gas mixture of Ar/CO$_2$ (3:1) and 40% CF$_4$, where CF$_4$'s high electron drift velocity enables time resolution in the order of nanoseconds (ns). CF$_4$ is a potent greenhouse gas, with a Global Warming Potential (GWP) ~7,000 times that of CO$_2$, and is subject to the EU F-Gas Regulation, with a phase-down that implies increased procurement costs and limited availability.
This study evaluates the µRWELL detector operated with different CF$_4$ concentrations and with alternative gases, to reduce and replace CF$_4$ in the gas mixture while maintaining acceptable performance. The experimental performance was studied with a setup installed at CERN's SPS H4 beamline, during several beam campaigns, using the DRD1 Thermal-bonded MicroMegas Telescope for data acquisition. The telescope can also be rotated for cosmic test outside beam times. Several gas mixtures were tested, systematically quantifying the effects of reduced CF$_4$ concentrations on the detector's performance and of CF$_4$ alternatives.
Between the two detectors tested, preliminary results consistently show that mixtures spanning 0% to 50% CF$_4$ have a time resolution difference of 2.5 ns. Notably, a 20% fraction of CF$_4$ limits the maximum time resolution by 1.3 ns relative to the mixture with 40% of CF$_4$. This change reduces emissions by 50%, significantly lowering CF$_4$ consumption and costs. Detection efficiency was compatible across the tested gas mixtures, with losses attributed to the DLC groove sectorisation and geometrical acceptance of the tested µRWELL prototype. Possible alternative gases, such as N$_2$, He, i-C$_4$H$_{10}$, and R-1234ze, are also under investigation.
| Name of the speaker | Stefania Juks |
|---|---|
| Eligible for the Georges Charpak Young Scientist Award. | yes |