Numerical study of track distortion in the Large Prototype TPC with end-plate based on bulk Micromegas

Deb Sankar Bhattacharya , Purba Bhattacharya , Supratik Mukhopadhyay , Nayana Majumdar , Sandip Sarkar , Sudeb Bhattacharya , Paul Colas (1) , David Attié (1) , Serguei Ganjour (1) , Aparajita Bhattacharya

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

The present R&D activities for the International Large Detector Time Projection Chamber (ILD-TPC) concern the adoption of the micro-pattern devices for the gaseous amplification stage. Seven Micromegas modules which are commissioned on the end-plate of a Large Prototype TPC (LPTPC) at DESY, were tested with a 5 GeV electron beam, under a 1 T magnetic field. During experiments, reduced signal sensitivity as well as distortion in the reconstructed tracks were observed at the boundaries of these modules. Electrostatic field inhomogeneity near the module boundaries was considered to be the possible major reason behind these observations. In the present work, this hypothesis has been explored using the Garfield simulation framework. It has been possible to contain the computational complexity of the problem with suitable simplifications. Qualitative and quantitative agreements with experimental results have been achieved. Possibility of mitigating the problems has been proposed using the same simulation framework.

Mots clés: K : Detector physics: concepts; processes; methods; modelling and simulations: Charge transport and multiplication in gas; Detector modelling and simulations II (electric fields; charge transport; multiplication and induction; pulse formation; electron emission etc); Gaseous detec- tors; Micro-pattern gaseous detectors (MSGC; GEM; THGEM; RETHGEM; MHSP; MICROPIC; MICROMEGAS; InGrid; etc); Time projection Chambers (TPC); electron: irradiation; time projection chamber; tracks; Micromegas; numerical calculations; electric field: effect; electric field: spatial distribution; Garfield; ILD detector; detector: design; track data analysis

Domaines: Instrumentations et Détecteurs [physics.ins-det]; Physique des Hautes Energies - Expérience [hep-ex]

Deb Sankar Bhattacharya, Purba Bhattacharya, Supratik Mukhopadhyay, Nayana Majumdar, Sandip Sarkar, et al.. Numerical study of track distortion in the Large Prototype TPC with end-plate based on bulk Micromegas. JINST, 2020, 15 (07), pp.P07030. ⟨10.1088/1748-0221/15/07/P07030⟩. ⟨hal-02572516⟩