Position-sensitive gas detectors: MWPCs and their gifted descendants

On the basis of concepts used in conventional multi-wire proportional chambers and drift chambers, another generation of position-sensitive gaseous detectors has matured for a variety of applications. Several limitations of multi-wire chambers have improved, sometimes by several orders of magnitude. The basis features and performance of some current devices are discussed: standard symmetric MWPC, MSGC, asymmetric structures (including MWPC, MICROMEGAS, CAT and MGC), secondary electron emission gaseous detectors and gas proportional scintillation detectors.