Abstract
In this chapter, the exciting developments in micropattern detectors in recent years are described. This includes GEM and MICROMEGAS detectors combined with micropixel readout, some peculiar designs of GEM and GEM-like detectors sensitive to UV and visible light, large area (>1m2) GEM and MICROMEGAS prototypes developed for the upgrades of the experiments at the large hadron collider, etc. A special focus is put on a new generation of spark-proof micropattern detectors, using resistive electrodes instead of traditional metallic ones. These detectors operate as ordinary micropattern detectors. However, in the case of occasional sparks, their current is limited by the resistivity of the electrodes so that the energy of the discharge is reduced by several orders of magnitude. Various designs of such detectors have been developed and successfully tested, including resistive GEM, resistive MICROMEGAS, resistive MSGC, etc. Among this family of detectors, a special place belongs to resistive parallel-plate micropattern detectors allowing one to achieve at the same time excellent spatial (38 µm) and time (77 ps) resolutions. Finally, the potential of multilayer detector technology for further optimization of the detector operation is discussed.
Top1. Introduction
Today, mainly GEMs and MIROMGEAS are used in high-energy physics experiments and in some other applications. One exception are the MSGCs used at ILL, Grenoble, for neutron detection. Consequently, a lot of efforts of the micropattern detector community were invested in various modifications of GEM and MICROMEGAS, for example development new signal readout methods, developing designs having large sensitive areas etc. in order to better fit the requirements of various applications. Most other types of micropattern detectors are still under development. In this Chapter the most important from these developments, performed roughly from 2004 to present time, are reflected. Earlier developments were described in Chapter 7.