A SELF TRIGGERED INTENSIFIED CCD (STIC)

We are developing a new device based on the results reported previously of the successful coincidence detection of beta- particles with a high spatial resolution [Y. Charon et al., Nucl. Instr. and Meth. A292 (1990) 179]. The novelty of the device consists in triggering and intensified CCD, i.e. a CCD coupled to an image intensifier (II), by an electrical signal collected from the II itself. This is a suitable procedure for detecting low light and rare events with high efficiency and high resolution. The trigger pulse is obtained from the secondary electrons produced by multiplication in a double microchannel plate (MCP) and collected on the aluminized layer protecting the phosphor screen in the II. Triggering efficiencies up to 80% have already been achieved.