Design of a small laboratory Compton camera for the imaging of positron emitters

A small laboratory prototype has been designed for the Compton imaging of a nnihilation photons produced from positron emitters. Considerations on the design of the scatter collimator are presented and the system configuration is described. The system features a stack of four AC coupled, double-sided silicon strip detectors (6 x 6 cm(2) area, 500 mu m thickness, 470 mu m st rip pitch, 128 channels/side) in a double Compton configuration and externa lly triggered readout mode. Signal readout is obtained by bonding two 128-c hannel low-noise APV6 chips to each detector. Custom electronics have been developed for the chip readout. The system is currently being assembled. Th e estimated angular resolution of the camera is approximately 4 degrees. Hi gh sensitivity could be achieved by extending the number of stack elements and by improving the design of the trigger detector, which presently consis ts of a small area germanium crystal.