Gas detectors: Recent developments and future perspectives

Thirty years after the invention of the Multi-Wire Proportional Chamber, and 20 from the first Vienna Wire Chamber Conference, the interest and research efforts devoted to gas detectors are still conspicuous, as demonstrated by the number of papers submitted to this Conference. Innovative and performing devices have been perfected over the years, used in experiments, and still developed today. Introduced 10 years ago, the Micro-Strip Gas Chamber appears to fulfill the needs of high-luminosity trackers; progress in this field will be reported, followed by a discussion on discharge problems encountered and possible solutions. Recent and potentially more powerful devices such as the micro-gap, narrow-gap and micro-dot chambers will be described. A new generation of detectors exploiting avalanche multiplication in narrow gaps has emerged recently, namely MICROMEGAS, CAT (Compteur a Trous) and the Gas Electron Multiplier (GEM); whilst still in their infancy, they have promising performances with increased reliability in harsh operating conditions. I will describe also some "tools of trade" used to model the counting action and to analyze the properties of the detectors, discuss limitations to their performances, and suggest ways to improvement. Several still controversial subjects of study las for example, aging), and imaginative efforts of the experimenters ensure a continuing progress in the held of gas detectors, and new editions of this conference for years to come. (C) 1998 Elsevier Science B.V. All rights reserved.