Design of a 10 nm electron collector for a track-nanodosimetric counter.

Recently we have developed a track-nanodosimetric counter, which is a gas detector that measures the distributions of electrons induced by a charged particle in nanometric volumes of tissue equivalent matter, positioned at different distances from the track. Sites equivalent to 20 and 24 nm were defined by means of an electron collector, which is a system of electrodes enclosing an almost wall-less cylindrical volume. In this paper, we present the design of a new electron collector that is able to simulate a volume as small as 10 nm in diameter.