Speaker
Paul Colas
(CEA/Irfu Saclay)
Description
A large TPC has been selected as one of two options for the main tracking at the Linear Collider. The LCTPC Collaboration has been conducting R&D in various directions for over 10 years. As a starting point, a Large Prototype consisting of a 72 cm diameter, 60 cm long field cage and an endplate with 7 windows capable of hosting 7 identical detection modules has been built and is operational since the end of 2008 in a superconducting magnet at DESY, for cosmic-ray and beam tests. Five amplification techniques are being studied in this setup and in smaller test devices: double-GEMs with 100 micron thick laser-etched GEM foils, Micromegas with a charge-dispersion anode, GEM read out by a TimePix pixellated chip, Micromegas grid integrated over a TimePix chip, and tripple-GEM with ceramic spacers. The main results from these various attempts will be presented.
In parallel, studies are on-going on the effect of the space charge created by primary ionization and by backflow from the amplification region. Assessments of the track distortions due to the drift of electrons in the resulting electric field and in the solenoid magnetic field will be given and the need for a gating device will be discussed.
Future plans, including power pulsing, electronic optimization and integration, cooling, and optimization of the mechanical structure, will be presented.
for the collaboration
LCTPC
Primary author
Paul Colas
(CEA/Irfu Saclay)
