Development of a TPC for an ILC Detector

The ILD concept, one of two proposed detector concepts for the planned International Linear Collider (ILC), foresees a Time Projection Chamber (TPC) as the main tracking detector. The LCTPC (Linear Collider TPC) collaboration pursues R&D to develop such a TPC based on the best state-of-the-art technology. After tests with smaller prototypes, the current efforts focus on studies using a large prototype with a diameter of 770 mm and a length of 610 mm. This prototype can accommodate seven read-out modules of a size comparable to the ones that would be used in the final TPC. Several prototypes of modules using Micromegas or GEM structures as gas amplification were constructed and tested. Besides the traditional pad read-out, a pixel read-out based on the TimePix chip is studied in these tests with up to 8 TimePix chips on a board. The current status and future plans of the R&D are presented.