G. Charpak et al., A HIGH-RATE, HIGH-RESOLUTION ASYMMETRIC WIRE CHAMBER WITH MICROSTRIP READOUT, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 346(3), 1994, pp. 506-509
We have investigated the properties of an asymmetric wire chamber with
cathode strip readout. The use of a small gap between the anode plane
and the cathode plane and of an electric field configuration provide
fast removal of the positive ions produced in the avalanche process an
d restrict the area of the induced signal on strips engraved on the ca
thode plane. We can thus contemplate using digital readout for these s
trips and still have good position resolution, or use analog readout f
or high spatial resolution. The detector can operate at very high gas
gain (10(5)); thus with a small gap of 2 mm we can achieve full effici
ency for minimum ionizing particles. We have measured no gain modifica
tion at a rate of 2 X 10(5) particles mm-2 s-1 at a gain of 10(4) with
a distance of 600 mum between anodes and cathodes and 500 mum between
anode and cathode field wires.