Two-phase emission detectors: foundations and applications

A new class of radiation detectors has recently been introduced into experimental practice. The detectors employ the effect of effective extraction of charge carriers from condensed non-polar dielectrics into the equilibrium gas phase under influence of an applied electric field. This approach makes possible to combine in one detector condensed detecting medium of a large mass, necessary for detecting rare events, with a rarefied phase, in which signals due to a few or even single electrons can be amplified and measured through gas-discharge or electroluminescence processes. We will discuss properties of working media that can be used in emission detectors, the physics of charge carrier penetration through the inter-phase boundary and we will also review applications of two-phase dielectrics for detecting ionizing radiation and exotic particles