Device to reconstruct positions of minimally ionising particles

摘要

This device to reconstruct positions of minimally ionising particles is characterised by the location of the two CCDs face to face and as close as possible, such that CCD1 is read from top to bottom and CCD2 in the contrary manner; as a complement to the CCDs, a trigger device 3 indicates the passage of a particle, recording its time with respect to a trigger oscillator (clock). This latter is in phase with the clock of the lines φp which together with φL (which extracts the charges cell by cell) run freely in both CCDs, in this manner obtaining a continuous readout. There is a period of integration or accumulation of charge for each line of cells equal to the time between two cycles of φp. The invention permits the use of the CCDs as very precise detectors of position in high-intensity pulsed particle beams, eliminating the dead time and the spurious tracks that were produced through series reading. <IMAGE>