Speaker
Andreas Bamberger
(Albert-Ludwigs Universitaet Freiburg)
Description
The combination of Micro-Pattern-Gas-Detectors and highly pixelated
readout provided by the MediPix2 chip and by the recently developed
TimePix chip demonstrates a new approach of the TPC-readout for the ILC.
For the DESY test beam of 5 GeV electrons the results of a triple GEM/
MediPix2 and a triple GEM/TimePix detector with 55μm readout pitch are
presented. Different gases (Ar/CO2, 70/30, He/CO2 70/30, Ar/CH4/CO2, 93/
5/2) are used. On average ≥8 clusters are recorded on a plane of 14 ×
14mm 3. Two configurations of the GEM stack have been used with transfer
gaps of 1 and 2mm. The induction gap is 1mm, the drift gap 6mm. The
point resolution of a cluster is determined by various methods being
between 30 - 60μm depending on the drift length. The new TimePix allows
the determination of the time of arrival above a given threshold and also a
charge measurement in each individual pixel (via time over threshold
information). In the mixed mode operation, where these quantities are
measured in a checker board configuration, the point resolution is improved,
moreover the 3-dimensional track reconstruction can be performed by using
the drift time information. The point resolution in the readout plane and the
features of the reconstruction of the drift coordinate are given for the triple
GEM/TimePix setup. The excellent double track resolution is addressed.
Author
Andreas Bamberger
(Albert-Ludwigs Universitaet Freiburg)
