Construction of a system for quality control of Thick-GEM type structures

• Grant number: 16/23355-7
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): December 01, 2016
• Effective date (End): November 30, 2017
• Field of knowledge: Physical Sciences and Mathematics - Physics
• Principal Investigator: Pedro Hugo Ferreira Natal da Luz
• Grantee: Lucas de Arruda Serra Filho
• Home Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 16/05282-2 - Development and applications of Micropattern gaseous detectors, AP.JP

Abstract

Thick-GEMs are structures of the type Micropattern Gaseous Detectors - MPGD - consisting of printed circuit boards with a thickness of 0.5mm, with 0.5mm diameter holes drilled in a hexagonal matrix with a pitch of typically 1mm. They work as radiation detectors by emerging them in a suitable gas mixture and by applying a potential difference between both sides, generating a very high electric field inside the holes. When this electric field is high enough, free electrons generated by the interaction of ionizing radiation with the gas mixture can be multiplied. This architecture has several advantages, such as the ability to use a cascade of more than one plate, where the charge amplified by one Thick-GEM can be further amplified by a second pr third. The Thick-GEMs designed by the group HEPIC@USP and produced by the Brazilian Industry must be subject to a quality control process, which will consist on the optical inspection of each piece, measurement of leaking currents in controlled atmosphere, determination of discharge threshold and documentation of several parameters of each structure for future reference. The assessment of the quality of each prototype batch is of major importance for the improvements necessary for each geometry and will also help keeping the quality standard of the production, allowing for a direct comparison between different structures, before installing them in a real detector. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

NATAL DA LUZ, H.; BHATTACHARYA, P.; FILHO, L. A. S.; FRANCA, L. E. F. M. Ion backflow studies with a triple-GEM stack with increasing hole pitch. Journal of Instrumentation, v. 13, JUL 2018. Web of Science Citations: 1.