Optimization of the Gas Flow in a GEM Tracker with COMSOL and TENDIGEM Development

F. Noto[1,2], V. Bellini[1,2], E. Cisbani[3,4], V. De Smet[1,5], F. Librizzi[6], F. Mammoliti[1,2], and C. Sutera[6]
[1]Dipart. di Fisica ed Astronomia, Università di Catania, Catania, Italy
[2]INFN – Sezione di Catania, Catania, Italy
[3]IINFN – Sezione di Roma - Sanità Group, Roma, Italy
[4]Italian National Institute of Health, Roma, Italy
[5]Haute Ecole Paul-Henri Spaak, ISIB, Bruxelles, Belgium
[6]NFN - Sezione di Catania, Catania, Italy

The Gas Electron Multiplier (GEM) technology has been proven to tolerate rate larger than 50 MHz/cm2 without noticeable aging and to provide the sub millimeter resolution on working chambers up to 45x45 cm2.

A new GEM based tracker is under development for the Hall A upgrade at Jefferson Lab. The chambers of the tracker have been designed in a modular way: each chamber consists of 3 adjacent GEM modules, with an active area of 40x50 cm2 each.

We optimized the gas flow inside the GEM module volume, using a COMSOL code. Our simulation includes design of the inlet-outlet pipes, maximization of the uniformity of the gas flux and minimization of the zones where such flux is too low.