Why do we flush gas in gaseous detectors?

S. Procureur (1) , D. Attié (1) , S. Bouteille , D. Calvet (1) , X. Coppolani (1) , B. Gallois (1) , H. Gomez (1) , M. Kebbiri (1) , E. Le Courric (1) , P. Magnier (1) , I. Mandjavidze (1) , N. Sellami (1) , R. Veenhof

1 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers

The effects and the origin of the gas degradation in a gaseous detector-based tracker are investigated. The study focused on the so-called T2K gas, which turned out to be highly sensitive to pollutants. In particular the H$_2$O and O$_2$ concentrations were monitored online in different conditions to establish their influence on the gain of the detectors. This pollution was first mitigated by a recirculating and accelerating gas system with the use of a turbine and different absorbers. Further measurements revealed that this pollution originates from a continuous permeation process through the different materials of the gas circuit. In particular, polyurethane-based gas pipes or polyester materials largely increase the level of humidity. As a direct consequence of this work, the gas autonomy of the muon telescopes currently deployed inside the Khufu’s pyramid have been dramatically improved.

Mots clés: ScanPyramids; Muography; Humidity; Micromegas; Gas purity; MPGD; Micro Pattern Gaseous Detectors

Domaines: Instrumentations et Détecteurs [physics.ins-det]

S. Procureur, D. Attié, S. Bouteille, D. Calvet, X. Coppolani, et al.. Why do we flush gas in gaseous detectors?. Nucl.Instrum.Meth.A, 2020, 955, pp.163290. ⟨10.1016/j.nima.2019.163290⟩. ⟨hal-02458764⟩