Advances in single-charge detectors and their applications

Modern gas avalanche detectors are instruments of choice for detecting sing le charges deposited in gas or emitted from thin solid radiation converters . We discuss principal factors governing the operation of gas avalanche pho tomultipliers, combining solid photocathodes with advanced micro-pattern ga seous multipliers and summarize the properties of UV photocathodes and film -protected photocathodes for the visible spectral range. We review recent p rogress and applications of single-charge counting detectors and discuss in some detail their application to nanodosimetry and its relevance to studie s of radiation damage to DNA.