Performance of MPGDs with portable readout electronics

A portable electronics solution for gaseous detector readout is being developed for use in high-rate tracking experiments or medical imaging applications. The frontend electronics makes use of the IDEAS VATA family of 128-channel charge-sensitive ICs coupled with the pitch-adaptor diode-protection circuit originally designed for the CERN TOTEM experiment. Each input channel of the front-end can be programmed for individual trigger and a global threshold with DAC adjustment can be used to achieve a uniform trigger over all channels. Chip programming and communication is controlled by an Altera-based DAQ which uses QuickUSB for the data transfer to the PC. The architecture of the system will be outlined along with a description of the analogue noise and lowest threshold for self-triggering, an important consideration for achieving efficient tracking of minimum ionizing particles. The system has been used with a 10x10cm triple-GEM detector equipped with an XY orthogonal readout board having 256 channels per layer. In Ar:CO2 (30%), an energy resolution of better than 18% FWHM has been obtained with an 55Fe source. The portable system is straightforward to use and makes a powerful laboratory tool. Work is being done to prepare the electronics for future applications at high rates above 500kHz. The results of the electronics’ performance will be presented and different tests will be performed to produce X-ray images of various objects.