Progress in low-pressure gaseous detectors

Abstract

Abstract Some outstanding properties of low-pressure MWPCs open new prospects in the domain of heavy as well as light particle detection. In the present mode of operation, the mechanism of avalanche formation is divided into two steps: it combines an amplification process in a high, constant, electric field region with a second one, occurring in the vicinity of the proportional wires. Large gains associated with fast charge-collection times are reached at pressures as low as a fraction of a Torr, leading to excellent timing properties and to a high counting-rate capability. Transmission timing detectors, having a total thickness in the 100 μg/mm 2 range, have been designed for heavy-ion detection and offer time resolutions of the order of 100 ps (fwhm) at rates as high as 10 5 c/cm 2 s. The properties of this type of detectors are summarized and localization and multitrack detection capabilities are discussed. Present and future heavy-ion detection systems based on this simple, efficient and low cost technique are described. Possible applications in nuclear and particle physics are also discussed.