Gain, Rate and Position Resolution Limits of Micropattern Gaseous Detectors

In this study we report the results of a systematic study of the gain, rate and the position resolution limits of various micropattern gaseous detectors. It was found that at low rates (<1 Hz/mm^2) each detector has it own gain limit, which depends on the size and design features, as well as on gas composition and pressure. However, in all cases the maximum achievable gain is less than or equal to the classical Raether limit. It also was found that for all detectors tested the maximum achievable gain drops sharply with the counting rate. The position resolution of micropattern detectors for detection of X-rays (6 to 35 kV) was also studied, being demonstrated that with solid converters one could reach a position resolution better than 30 micrometers at 1 atm in a simple counting mode.