Use of TMAE in a multistep proportional chamber for cherenkov ring imaging and other applications

Abstract

We tested a multistep proportional chamber of 20 × 20 cm² activ area, conceived to localize single vacuum ultraviolet photons. The detector has a capability of imaging large multiplicities of Cherenkov rings with a high density of detected photoelectrons and uses tetrakis(dimethylamine)ethylene, with a threshold of 5.4 eV, as the photoionizing vapour. Time slicing in a conversion gap reduces the multiplicity at a given instant of time by a large factor and permits the use of simple methods of localization. Separation of the amplifying gaps solves the problems of photon feedback encountered, at high gains, with single-step detectors. We also discuss an application of this chamber for the detection of superheavy monopoles if they have a speed in the range of the electron drift velocity.