PACEM: a new concept for high avalanche-ion blocking

• Author(s): Veloso, J. F. C. A. ; Amaro, F. D. ; Azevedo, C. D. R. ; Santos, J. M. F. dos ; Breskin, A. ; Lyashenko, A. ; Chechik, R.
• Date: 2007
• Persistent ID: http://hdl.handle.net/10316/4347
• Origin: Estudo Geral - Universidade de Coimbra
• Subject(s): Gaseous electron multipliers; Gaseous photomultipliers; VUV scintillation; Photocathodes
• Document Type: Article
• Language: English

Description

We present the Photon-Assisted Cascaded Electron Multiplier (PACEM) as a potential alternative for ion back-flow suppression in gaseous cascade electron multipliers. Using a Micro Hole and Strip Plate-Gas Electron Multiplier (MHSP-GEM) configuration, the number of ions flowing back to the scintillation region is about 1.5 ions per primary electron at an optical gain of 6.5 and a drift field of 0.1 kV/cm, and about 10 ions per primary electron at an optical gain of 10 and a drift field of 0.5 kV/cm. These allow reaching ion back-flow values close to 10-4 and 10-5 at typical operation conditions of TPCs and GPMs, respectively. http://www.sciencedirect.com/science/article/B6TJM-4PB0PFX-15/1/9e6f704a6503d50bc4b54966701688c4